Level 80-85. There are two options to OSRS gold choose from: stick with Yew Longbows, or switch to Magic Shortbows. If you're buying the logs, I recommend Magic Shortbows as they give more knowledge. If you are cutting the logs yourself, it is faster to use Yew longbows instead of Magic Shortbows. Magic Logs take much longer to cut.

If you decide to continue using Yew longbows, you will need 848 of them. You will need 7,620 Magic Shortbows to progress to level 85 in order to create Magic Shortbows. Congratulations! I'd like to and do another thing for a while perhaps alchemy or even sell the bows you made just to buy yourself something nice, or train other skills. Only serious fletchers are allowed to continue past this point.

Level 85-99. If you're determined to reach level 99, you'll need to create 53.420 Magic Longbows. Yes, it's a lot but don't get discouraged by it. It's possible. It could earn millions of dollars if you really would like it to buy RS gold.