I'm pretty brand new to knitting. Please help! The pattern reads:

(P1, YO, P1) in next stitch

What does in next stitch mean? ARGH!
I have a feeling this is going to be really easy to explain but it stumped me.

You're going to be increasing in the next st - purl it, but leave on the needle, wrap the yarn for a YO, then purl again and your stitch is complete.