If you're up to a complete bare-frame, last nut and bolt restoration, allow me to share some tips-
1. Tear down can be as important as assembly. Take pictures. Lots of pictures. High quality pictures, and store them on your computer. It may be a year or two before you reassemble. You ain't gonna remember where that little bracket goes, or how that wiring harness was routed. 1 gallon Zip-Lock bags are your friend. Put all the small pieces, hardware, etc. for every sub-assembly in a labeled bag, so they are all together.
2. Get a service manual!! You'd be surprised how many are free PDF files online.
3. Get a COLOR wiring schematic. Probably in the above manual. Even as your bike is a fairly simple model, you're not gonna remember where all those wires go, and the connectors aren't generally made idiot-proof like they are in cars.
4. It's easy to get overwhelmed. It's like eating an elephant, one bite at a time. Like, "Today I'm gonna rebuild the rear brake. Tear down, clean, paint/polish, reassemble, back in the bag for re-assembly time."
5. Decide early on if you're repainting and re-chroming pieces. This ain't cheap, and while you MIGHT be able to do your own painting, I don't think there's anything like "DIY chrome". The chrome bill for that 90 was $1300, The 200 I'm doing now is $1700. Searching for a reputable chrome or paint person can be a project by itself.
6. When tearing down, DON'T THROW ANYTHING AWAY! This goes for O-rings, gaskets, grommets, etc. You may not be able to buy new, you might have to match it up with something at the hardware store, or even make it yourself.
7. Take your time. This ain't something that's gonna take a weekend. This is a long-term relationship, and there'll be times when you have to step away. You don't have to drive this thing to work tomorrow, so there's no rush.
HTH. If I think of anything else, I'll add it. Don't let me discourage you! Like I said, if you take your time, avoid shortcuts, the finished product will WOW people. You will also have a better appreciation for someone else's restored car, motorcycle, etc.