follow the instructions on the bottle of F10sc.
If you have a 1 L spray bottle , fill the little reservoir to the bottom line , and pour the contents into the 1 L bottle , add tap water and shake well , it's now ready to use .
Only need spray a thin film onto the surfaces of the things you want sterilized .... then wait 20 mins , and wipe dry with paper towel , or simply let the sterilized F10ed thing airdry , and you're done.