Have you thought about it, and figured out squares are certain?
Good, because my answer is here. Green dots are clear spaces. Red dots are crystals.
Does my answer match yours?
If you've found any mistakes, please message me with the details. Thanks. Now scroll down.
Oh, yes, since you're with me this far, I have a couple more hints.
1. If you have to guess a square to click, pick one that will give you information, even if it explodes a crystal. Breaking a crystal next to numbers that make you say, "Oh, now I know which other ones are clear" is much more useful than breaking a crystal out in the middle of unbroken blue squares.
2. If you can, pick a square that you know is a crystal, one that is off by itself, and leave it alone until the end of the game. If you end up with a couple blue squares that do NOT have crystals under them, the unmarked crystal gives you the chance to clear them before Meep declares the game over. - "Why do that?" you may ask. Your score is all the numbers you uncover, added together, and then 10 points for each unbroken crystal. The numbers that are still covered at the end of the game don't get added in.