Hi Craig,
Practice and more practice, keep trying it out on your own home.
Clean some of your family and friends house for free. As they are friends you can at least go inside and have a coffee and a chat, wait for the windows to dry to see how they have turned out and go over them again until you are happy.
Friends and family should be only too happy to get a free clean, and they can hardly complain about a few spots!
Don't rush out and start on the paying customers until you are comfortable with all aspects of the equipment and its usage.
First time cleans will always take longer, use more water (A lot more!!) and be harder to get perfect.
Thoroughly wash the frames and then the windows on first time cleans. I personally have a higher than normal flow rate and will do all of the upstairs then go back over it again before I start on the lower windows.
If the windows are aluminium or wood framed, wet a figer and check that the frames are not oxidized, if your finger comes away white then that will be a real problem clean, and always will be until the windows are repainted or replaced.
Either do them the traditional way or drop them.
Best of luck! Once you get in the swing of things you will never want to climb a ladder again
It is early, it is dark, it is hammering down with rain and the wind is howling outside
............I am going to get very wet
The weather so bad I think I will have most of the day off
The rain isn't the problem, it is the wind that will mess up the windows
Not often the conditions will stop me doing my shops and pubs
Will today though
Ian