Level 40-55. I would recommend going to Seers’ Village from this point on. Seers' Village is the most suitable location for those who are at or OSRS gold above. If you're cutting your own logs, cut in the spot on the map above for willows. Then, you can create 3,082 Willow Longbows (u) for 55 fletching.

Level 55-70. This is the most challenging and lengthy stretch. It's the place where you'll string all your bows. They will give you more exp this method. As you progress to level 70 you'll have to construct 4,881 Maple Longbows.

Alternative: Instead of strunging all of buy RuneScape Mobile gold these bows and fletching them, you could purchase twice the amount of logs, and then simply flytch the bows. This would significantly reduce the price, according to Grand Exchange prices. This strategy can be used even if you don't have many coins, however you can reduce the cost a bit.