Advertising wherever you can without spamming or being obnoxious helps a ton. For example for my game, (https://itch.io/jam/brackeys-5/rate/927134) I've been putting links all over the place. Another thing that helps is giving detailed feedback in a positive way, for example stating an issue that a game has, and how to fix it will make people more inclined to want to help you in return.
One last thing, in these community posts, if you make a topic asking to play games instead of a rate for rate, it gives more opportunities to use thee feedback thing mentioned earlier, because some people want theirs to be rated without having to rate another game, and a post like that would bring them in as well.
I hope that makes sense lol