There are many different features you should look for in a good set of shin guards:
Length - Check with your league’s rules. Some require a minimum length of soccer shinguards in order to play.
Protective material - What are the guards made out of? Go for the most lightweight, breathable, and unbreakable material you can find. Ask around to see what your friends are using and if they’re satisfied.
Outer cloth - What outer cloth are they made out of? Make sure it is durable yet breathable.
Ankle guards - These are a must have for younger players, yet not as essential for experienced players. Make sure they are plastic ankle guards, cloth does no good.
Also see how the shinguards from Uhlsport, Lotto, or whatever brand you pick, stay on your legs. You can either use Velcro straps, tape, or a Nike shinguards sleeve.
If you can’t tell, there is a lot of concern on keeping your shin guards from containing moisture and heat. These factors can lead to cramps in your legs and poor performance. Definitely give Uhlsport soccer shinguards a look, you won’t be disappointed.