What is the most logical next event?

How to buy alcohol for your party 
Set a budget. 
Before you can think about who to invite and how much alcohol to buy, it's important to set a budget for your party. This can help you not overspend and guide you what types of alcohol may be best for your party.
Let how much money you want to spend overall guide you. For example, if you can spend $150, you may want half to go to alcohol and the other half to food.