Odd tan lines are due to long sun exposure in a specific cut of clothing. By mixing up what you wear, you can expose different parts of your skin to the sun to help even your skin tone out. For example, alternate between a tank top and T-shirt so you can avoid getting a tan line across your arm and neckline. You can even consider wearing loose-fitting long-sleeve shirts or pants to keep your skin covered from the sun. The sun is most intense from 10 a.m. to 2 p.m. standard time. If you find yourself outside during these hours, try standing in the shade as much as possible. If shade is not an option, try keeping your skin protected with either clothing or sunscreen. The best way to protect your skin and stop unwanted tan lines from forming when you are out in the sun is to wear SPF 30 or higher. Even after you have seen the effects of the sun on your skin, continue applying sunscreen so your tan lines don't become even darker.  It takes thirty minutes for sunscreen to absorb into your skin and start protecting you from the sun's UV rays.  If you know you are going to be outside in the sun all day, continuously apply sunscreen to your exposed skin every hour to prevent a farmer's tan from occurring.

How would you rephrase that briefly using Vietnamese?
Mỗi ngày mặc quần áo nhiều kiểu khác nhau. Tránh ra nắng khi tia UV đang hoạt động mạnh nhất. Ngăn ngừa cháy nắng bằng kem chống nắng.