That green letter doesn't look fabricated. It's a bit of an art making acrylic fab letters. You generally use 3mm acrylic, make a pattern on paper whatever and use a heat gun and a heat strip made from heating elements, a neon ribbon burner, self made type of oven thing to heat long strips to form long curves, etc, etc. . You use bits wood, wood patterns, pipe, anything to get the curves right and you generally only get one go at forming curves.
Those chinese heat things aren't for bending acrylic. They are for bending that cheap plastic stuff they use. Acrylic needs a lot of heat.
Letters only made up of straight sides aren't that difficult but O, S etc and anything with a serif is way more difficult.
You're best bet is to spend a day on youtube and watch a lot of videos to see how some do it and you'll get a gist of what is required.
You'll need the thin glue, thisk glue, heat gun, hand router, assorted stuff. I generally score and snap the lengths but you can get a small slide saw.
I've never liked making them and avoid it these days.
Good luck.