user10030: How do you deal with this? I'm a bit of a chess perfectionist, and I always want to play the best move, so when I go up against an irregular opening, I don't do badly, but it's hard be 100% sure you made the best move in the opening, and that really bothers me psychologically.
My current method for dealing with these types of situations is to just follow the basic opening principles, but at my level I feel like this is not detailed enough or too vague, since I always try to strive for a certain level of understanding in every position. What can I do to be more flexible in this area of chess? Are there more detailed guides for playing against uncommon openings?
Even though I don't necessarily play badly, I really want to learn to be "comfortable" in all positions. How would I achieve this? Is the answer to play beginners since they tend to play strange openings all the time? I've already done this, but I still don't seem "comfortable" enough. Maybe its all in my head? 

user9030: You are prepared for popular opening lines as you studied guides about them, but you are lost when you are out of the book. This indicates that you lack opening strategy and piece improving skills and you should work on  them. 
Memorizing and playing best opening moves won't help you to improve your chess. Actually, if you don't understand why a particular move is the best, you can't take advantage of resulting position. Let's say you played perfectly in the opening, after the opening you are on your own and you have to take advantage of resulting position, but you won't be able to as you don't understand deeply what you achieved in the opening so far. So instead, you should improve your overall chess ability to be able to play in any random position.
For this very reason, Fischer suggested 960Chess. He was complaining about that chess is getting more and more an opening memorizing game.

user11629: If you face something unexpected in the opening it is important to stay calm. It is unlikely that the new move is a super-strong novelty which will make you lose immediately. 
Also you should avoid getting into the opposite mindset. We all know that things like the Grob are bad for white, but this does not mean that you can easily refute it and get a winning position. In many cases what you get even with perfect play is just a small advantage.
From a chess point of view, if you don't know theory you have to play on general principles and avoid tactical traps. Training both of these will help you not only when you encounter new openings, but also when playing the openings you know after you run out of book moves.
Also in many cases, particularly in less ambitious irregular openings, you can just play a system that you are familiar with: e.g. (depending on the situation) a Sicilian dragon setup or a Kings Indian or...

user13012: I used to play 1.b4 with some regularity and success. It worked extremely well against two kinds of opponent. One kind reacts by going on the defensive, and playing safety-first moves which give them a cramped position. The other kind believes that they can find a refutation over the board, consumes a great deal of time, and eventually gets nowhere (I would not play anything actually known to be refutable.) 
The sensible reaction is not to get into obscure tactics that your opponent
is likely to be prepared for. However, if you play well, you are probably under less pressure than you would be in a mainstream opening. So you may be able to choose slightly more aggressive piece placements than you normally would, such as Bd6 rather then Be7.
If you allow your normal thinking style to be disrupted by an unusual opening, then your opponent has already achieved one of their main objectives

user-1: What you describe is the best advice to meeting an unusual opening: play by the principles.
In terms of resources, there are 2 I can think of:

Beating Unusual Chess Openings by IM Richard Palliser. By 'unusual', Palliser really means anything other than 1. e4 or 1. d4, so he covers from Black's point of view: 


The respectable (English Opening, Reti and King s Indian Attack) through to the offbeat (Nimzo-Larsen Attack, Bird s Opening) and the totally bizarre (Orang-utan, Grob)


Chess.SE. We are always happy to see questions such as What are the ideas behind the Blackmar-Diemer gambit?


10030: <p>How do you deal with this? I'm a bit of a chess perfectionist, and I always want to play the best move, so when I go up against an irregular opening, I don't do badly, but it's hard be 100% sure you made the best move in the opening, and that really bothers me psychologically.</p>

<p>My current method for dealing with these types of situations is to just follow the basic opening principles, but at my level I feel like this is not detailed enough or too vague, since I always try to strive for a certain level of understanding in every position. What can I do to be more flexible in this area of chess? Are there more detailed guides for playing against uncommon openings?</p>

<p>Even though I don't necessarily play badly, I really want to learn to be "comfortable" in all positions. How would I achieve this? Is the answer to play beginners since they tend to play strange openings all the time? I've already done this, but I still don't seem "comfortable" enough. Maybe its all in my head? </p>
 9030: <p>You are prepared for popular opening lines as you studied guides about them, but you are lost when you are out of the book. This indicates that you lack opening strategy and piece improving skills and you should work on  them. </p>

<p>Memorizing and playing best opening moves won't help you to improve your chess. Actually, if you don't understand why a particular move is the best, you can't take advantage of resulting position. Let's say you played perfectly in the opening, after the opening you are on your own and you have to take advantage of resulting position, but you won't be able to as you don't understand deeply what you achieved in the opening so far. So instead, you should improve your overall chess ability to be able to play in any random position.</p>

<p>For this very reason, Fischer suggested 960Chess. He was complaining about that chess is getting more and more an opening memorizing game.</p>
 11629: <p>If you face something unexpected in the opening it is important to <strong>stay calm.</strong> It is unlikely that the new move is a super-strong novelty which will make you lose immediately. </p>

<p>Also you should avoid getting into the opposite mindset. We all know that things like the Grob are bad for white, but this does not mean that you can easily refute it and get a winning position. In many cases what you get even with perfect play is just a small advantage.</p>

<p>From a chess point of view, if you don't know theory you have to play on <strong>general principles and avoid tactical traps</strong>. Training both of these will help you not only when you encounter new openings, but also when playing the openings you know after you run out of book moves.</p>

<p>Also in many cases, particularly in less ambitious irregular openings, you can just play a <strong><em>system</em></strong> that you are familiar with: e.g. (depending on the situation) a Sicilian dragon setup or a Kings Indian or...</p>
 13012: <p>I used to play 1.b4 with some regularity and success. It worked extremely well against two kinds of opponent. One kind reacts by going on the defensive, and playing safety-first moves which give them a cramped position. The other kind believes that they can find a refutation over the board, consumes a great deal of time, and eventually gets nowhere (I would not play anything actually known to be refutable.) </p>

<p>The sensible reaction is not to get into obscure tactics that your opponent
is likely to be prepared for. However, if you play well, you are probably under less pressure than you would be in a mainstream opening. So you may be able to choose slightly more aggressive piece placements than you normally would, such as Bd6 rather then Be7.</p>

<p>If you allow your normal thinking style to be disrupted by an unusual opening, then your opponent has already achieved one of their main objectives</p>
 -1: <p>What you describe is the best advice to meeting an unusual opening: play by the principles.</p>

<p>In terms of resources, there are 2 I can think of:</p>

<ul>
<li><a href="https://www.amazon.co.uk/Beating-Unusual-Chess-Openings-Annoying/dp/1857444299" rel="nofollow noreferrer">Beating Unusual Chess Openings</a> by IM Richard Palliser. By 'unusual', Palliser really means anything other than 1. e4 or 1. d4, so he covers from Black's point of view: </li>
</ul>

<blockquote>
  <p>The respectable (English Opening, Reti and King s Indian Attack) through to the offbeat (Nimzo-Larsen Attack, Bird s Opening) and the totally bizarre (Orang-utan, Grob)</p>
</blockquote>

<ul>
<li>Chess.SE. We are always happy to see questions such as <a href="https://chess.stackexchange.com/questions/14035/what-are-the-ideas-behind-the-blackmar-diemer-gambit">What are the ideas behind the Blackmar-Diemer gambit?</a></li>
</ul>
