Don't listen to Empl0de32, the fishing minigame is fine as it is. If you don't like it there's a rod that makes it easier.
As for tips, just keep in mind what the community center needs in the beginning and don't focus too much on finishing one thing. Also set goals for yourself to achieve to keep you from getting bored.
A popular challenge is getting the community center done within the first year. It used to rely on luck because Red Cabbage Seeds aren't sold in year one so you need to get lucky to buy either the seeds or a red cabbage at the traveling merchant to do this but now theres a new setting in the advanced options intruduced in 1.5 that can guarantee you will be able to buy a red cabbage seed in year one. Don't worry about diluting the challenge, it's still plenty hard, just removes the one RNG part.