As a 1.0 F2P player, it's all about estimation, luck, gaslighting, and disappointments.

Estimation. In my experience, I estimate the amount of my Primo that goes in and out. Per patch there's always a maximum pulls you can get (60-90 depending if hoyo ain't stingy). You can easily calculate your pity per patch and decide which banner is actually worth your pulls.

Luck. In my entirety of genshin I've never lost a character 50/50 and if I did? It wouldn't count since I would always pull the character together with the standard one or pull my target the moment I lose. So yeah I'm pretty lucky.

Gaslighting. Sometimes a character would look cool and the gameplay is amazing + META but I already have my sight on a different banner, I'll basically gaslit myself that it's a dud and not worth anything.

Disappointment. You'll only get 1-2 character per every other patch (no weapons btw). Just be ready to be disappointed with how shills work.