It can be difficult to decide what the best flash games are. There are so many different games that you can choose from you see. You will also find that what you like in a game, is different to what other people like and so it is impossible to say which is the best.
However, if you want to know which are the best games, then it is a good idea to read some reviews. You will find plenty of them around. Although they will only let you know what other people think of games. They will be more useful than not reading reviews at all. You will get to know a bit more about that game and what the good and bad things are about it. This should help you to decide whether you think that it is a game that it is worth you trying.
Of course, you could just try lots of games and decide for yourself, but this can take a lot of time and some people would rather not do this. You may have a favorite genre of flash game and this will help you to narrow it down somewhat. People tend to have preferences such as liking babysitting games, puzzle games, fashion games, racing games, get ahead of the games, arcade games or whatever and even if you like several categories, there will be some that you do not like and will be able to eliminate from your search.
You should be able to gather enough information about what flash games are available, what others think of them and which types that you like the best to be able to draw conclusions as to which games are worth trying. You should be able to get an idea of which the best games are, but as there are always more and more games being written, then it is a good idea to keep up to date with new games arriving as you may find that you change your mind about which is the best!