This page offers a breakdown of the DIY recipes for Nets.
The Flimsy Net DIY is first given to you by Tom Nook when you complete the DIY workshop during your first couple of days on the island. You will also be able to buy a Flimsy Net DIY from Timmy at Resident Services or later at Nook’s Cranny.
To craft a Flimsy Net, you need 5 tree branches, which are obtained from shaking trees.
The Flimsy Net is very fragile and will break after catching a few bugs.
You can purchase the Pretty Good Tools from the Nookstop in Resident Services for 3,000 Nook Miles. To craft the standard net, you’ll need to first craft a flimsy net and then use iron nuggets to upgrade it at the craft bench. You can obtain iron nuggets from hitting a boulder with a shovel.