Yo K2tog isn't working

#1

I am fairly new to knitting and am knitting a shawl that should be relatively easy (except that it is long) because it is the same stitch pattern over and over. Some rows are all knit and some are yo and either k2tog or p2tog. I have just messed up a yo k2tog patch (for the umpteenth time) and need to know where I can get a book or website that will visually show me (step by step) how to fix this (hopefully) without having to rip out entire rows of stitching. HELP PLEASE

#2

Can you tell us what it is that you messed up on?