beginner crocheting help please!

And when I say beginner...I mean beginner. I'm so new at this but I am trying. The lady from my church that's showing me how to do this is stumped also so I'm really hoping someone from here can help. Okay, here's the problem. I've been attempting to crochet a baby blanket for a gift for several weeks and every time I start I get about 3 rows done and I get completely stumped. The pattern has a ripple affect on it and it switches colors every so many rows. Well, I've pretty much given up on that concept so I purchased yarn that is already multicolored. I've figured out how to make the "ripple". It only took me a couple weeks to figure that out. (feeling dumb here) I've managed to get about 3 rows and according to the pattern I can "finish off" and "with right side facing and working in both loops, join White with slip st in first dc; slip st in each dc across", then switch back to my original yarn. HELP!!! I certainly don't want to start over again cause I've never gotten this far. I know how to single, double, chain, yarn over, ummmm..I think that's it. Can anyone help?

Thanks in advance!!

"T" :)