Honestly it's not interesting at all. Do a few searches and thousands of preints, plans, drawings. material lists, and directions will come up.
Short and sweet.
3 sheets of 3/4" or 1" high ply ist grade plywood, some recommend special hardwood ply only, like a furniture grade oak.
a lot of 2x4's
screws whether they are stainless or not.
a sheet of glass or acrylic about 4'x8'
some use sheets of fiberglass and resin.
Some paint the resin with a marine epoxy, some skip the fiberglass and only use epoxy.
cut one sheet of ply in half 4x4
Lay one sheet down so it's flat, the 4x4 sheets will be the ends on the 4' side of the ply. Prop up the 8x4 remaining piece along the back. You now have the general tank, 8x4x4. You want to use 2x4 studs about one every 12" as a skeleton. You screw them in place so that the skinny side sticks out. Generally you glue them before screwing. The tanks I saw had the 2x4's stick out about 3 1/2" so that they can overlap and be screwed together. The bottom had 4 2x4's on their sides screwed under the sheet stciking out the 3" or so. Then the 4x4 sides had 4 studs runnign down and extending 3". This way they overlapped and could be screwed together giving it strength. Once you do this all the way around you add one more full elntgth 2x4 to the outside edge of the back bottom area. this way you have a runner that the 8x4 back piece can attach the 2x4 studs to. Once it was all framed together and the glue dried you begin on the glass. I saw a lot of tanks that had a 2x6 frame built to fit the front of the tank. Once that is positioned the entire inside was laid with fiberglass sheet and the proper amount of resin was applied. Pay special attention to where the glass goes , carefully wrapping the resin and sheeting around the 2x6. When that's all cleaned up you silicone the glass into place. When that dries you silicone more 2x6 to the inside overlapping to the original studs. This leaves a place to run screws through sandwiching the glass. Once that was done you fiberglass over the new studs to protect them.
Would I do it? Probably not. Seems like a lot of work. If I was going to do it I'd have to build at least a 1,000g tank. Used tanks can be had for a reasonable amount of money. I knew a guy that spent almost $1,000 building his own 90g. I asked him why? He said it was because he built it into the wall. Sure enough he did. But then again wouldn't a $200 90g complete with overflows have just as easily been slid into that same hole?