Seems like a decent way to make a pleated, cylindrical filter element. It's definately not the only way. The 'best' way has to be determined by you.
Start by doing a google search for aftermarket intakes for Supra's. Collect a few of your favorite images, and use them for references. If you like, post them here and ask for specific advice for how to try stuff. You'll get more help if you ask specific questions. Instead of asking-
"hey, how do I make an intake", ask
"Hey, I found this(these) pics of intakes, and I want to build one to look kinda like this-
- -how do you think I could make the...."
But first, you have to do the research, and figure out what you want to build.