I don't want to come off as rude but there are plenty of threads here on the topic of roof raising.
I would recommend looking at some, get an idea of what needs to be done and yes, then ask questions.
I myself have done two roof raises, really not that hard but it is labor intensive work for sure.
If you can do simple welding then you can do a roof raise but I would not try it without reading some of the threads here in the forum.
Here is one of my threads, there are many more really good ones here...
No "ONE" method is right or wrong, just different ways of skinning the cat.
Whatever route you take, read the posts and get sum freee edumecation !!!