You will soon have some replies that will show you some risk assessment examples, ditto method statements, or they will post the links for you.
As Poleman said, currently ladders are still ok, and I personally think that learning window cleaning the trad way is the best way to go.
Should you use WFP you will still need all the trad skills, so stick with it.
I'd steer away from 3rd floor work though, and if you are also new to working off ladders...take care!
There are many do's and don'ts with safe useage of ladders, I don't have the time this morning to post the links to the relevent health & safety docs, but hopefully someone will.
Ian