A good tip of advice I heard early on (which really resonated with me) was to value bet your
hands more and
bluff less.
Naturally, everyone should adapt when necessary, but people don't always bluff as much as you think and we still want to get paid when we do hit our best hands.
p.s. I also recommend the 30 Day course mentioned in the post above. My result in that course freeroll game makes me biased
but even if it wasn't for that great experience, I'd still recommend this course. It has a lot of quality information and I love how it was presented