Lucy,
Good to hear you are starting off, where in Hampshire are you, I used to be based at Middle Wallop in the 80's.
My best piece of advise is....... try and find a window cleaner on this forum who lives reasonably close to you and spend a day or two with him/her. You will be amazed how much you will learn from just working with him/her for a short time.
You're more than welcome to come and spend a day with my lads.........but we're up in North Northumberland and if you are feeling the cold in Hampshire then trust me, you don't want to be cleaning windows up here at the moment.
Bit more advise, use a BOAB and pouches and also get one of the Unger zip up pouches for keeping your book or PDA and money in. Once you have a reasonable sized business invest in George and a pda, well worth it.
Good luck
Ian