How do you restore your IPod touch without losing everything?

there are 2 ways

one way is that if you already have all your apps synced on itunes then no problem

or the best way, that you download ifunbox (search for it on Google) and it is an ultimate iPod/iPhone filemanager. just copy paste all your files to the CPU :D

hope it'll work

P.s I havent tried the first option so best if you try the second option