While copper is so malleable it's quite easy to make lines by hand, if you have tighter bends (like the loops some favor) you stand a chance of flattening/kinking the tubing or just irregular curves.
The least expensive brake/fuel line tubing bender is simply a spring with the same ID as the tubing's OD, slipping it over the tubing it helps prevent distortion while bending. Flaring & cutting tools are also ofc handy lol
Given ya can get a basic kit w/all of the above for like $12 ya might wanna consider something like this: Amazon.com: Pipe Cutting + Flaring Kit - Cutter, Bending Springs, F: Home Improvement
although it's great for copper & even mild steel, if yer considering stainless you'll wanna kick it up a bit and get some bending pliers like these: Amazon.com: Powerbuilt 648485 Deluxe Tube Bending Pliers: Home Improvement
Such small tubing is handy for other things as well ofc, I used it w/flared ends (to prevent wire chafe) to route the wiring for my hub genny & lighting to keep things tidy;