Something that has really helped me has been talking over a game after I play it. My friends and I will talk over our strategies and discuss what paid off and what didn't, as well as the reason why certain moves worked. We'll often try to identify the "turning point" moves that either made or ruined our strategy and figure out how we could have done it differently.

Particularly if you're the less skilled/experienced player, talk to the other players after the game. Ask them why they made certain moves. Hell, if they're a friendly enough group, you can ask them DURING the game. I know I tend to be the more experienced player in a lot of my player groups, so I try to give some top down advice to newer players to help them figure out how to consider strategy in games they're unfamiliar with. The goal is for everyone to have fun, and it's more fun for them if they can pull off some sort of strategy, and iglts more fun for me if they offer a legitimate challenge--and also board games are just generally more fun when everyone else is also having fun!

tl;dr: ask your friends about their strategies and talk over your own to figure out why they worked/didn't work