You gotta spin the disc. Like no really you really need to flick the FUCK out of it. So much spin.
Throw more. This should probably be the first thing. Also you need a really big field to practice. If it's too small you will find out very quickly.
Play with friends if at all possible. It's more fun, and it really helps when you're looking for your disc in the bush.
I don't keep score. Once I'm over par I'm just doing my best. But if I par or birdie, yay! Total score? Who knows.
If you bring a snack, bring something you can eat with dirty hands. Your hands are always dirty during disc golf. Snack bars, the answer is snack bars. Store brand.
Bring clothes you're ok sweating in and, importantly, ok digging around in bushes in. This sometimes means thorns! Hopefully not! Just don't bring anything you super super like.
If you have shoes that are in any way water proof: those are nice. It's really sketchy trying to get through very very small creek beds in my sneakers without wet socks.
If you're new and looking at how there's 10,000 different discs: you want the 3 disc innova starter set. The one with the aviar, shark, and leopard. Not the 5 disk, that one is terrible. 3 is plenty, it will take you a good while to be able to throw any of them well. You can and should throw the putter for drives starting out. Don't fall down the hole of gear. Bring a backpack or an old tote bag. You could just carry 3 discs but then you have no room for snacks and water....
Yes you will take big chunks out of the discs sometimes. As long as they're comfortable to throw, they're perfectly fine. You can snip off little pieces that stick out if you must.