As said before applicator etc , as for rubbers i use pulex medium i think , some say soft in winter ettore , because of temp affecting rubber , blade size most of time 12inch , . you need to practice , slow at first get technique right , i used to practice at home , make sure rubber is not damaged makes abig differance , i was lucky ihave worked with some good window cleaners , see if you can spend a day with a windowcleaner , we have all been there , failing all that im sure there are courses you can go on , practice master. , all best bob.