This is a great way to practice doubleknitting. Doubleknitting has been around at least since Hoover's time- see Hoover blanket-but I would practice with a potholder first. You really don't need to make a wide border for potholders but can make the whole thing in doubleknit and it will make a nice thick potholder.
Materials: WW yarn in two different colors, straight knitting needls size 6-I'm using RHSS but you can also use S&C cotton and also get a nice thick dishcloth.
Crochet hook if you want to make a loop in corner.
Gauge is unimportant.
Note, try not to twist your yarns together while knitting except at the beg of rows (where you'll twist them tog once to keep edges together), with practice you can do this quite easily.
There are several ways to cast on for this, I like two ways: With the darker color, CO double the number of sts you'll need for your project (30 would be a good size so CO 60)
Alternate method: Holding both colors together CO 30 sts-making sure your colors always fall the same way-dark/light or light/dark
Start your doubleknitting-holding both yarns tog, K the first st with your first color, bring both yarns to the front and P the next st with your CC, bring both yarns to the back, K the next st-always alternating colors. Continue in this manner to the end of row.
Next row, you will be K the sts you P in the prev row and P the K sts. Twist your yarns tog once before starting.
Continue in this manner until potholder/dishcloth is the size you want. BO by K2tog across-still using both yarns. At the end of the BO insert crochet hook in the st left and ch 1, sc evenly around potholder. When you reach the beg of your border ch 10 and ss in first sc. End off and tuck in all loose ends.
If you've done this correctly you will have a potholder/dishcloth that is one color on one side and another color on the other. When you get accustomed to this method you can start working patterns into your project which, when finished, will be opposite images of each other on each side. To work stripes you would alternate your colors every few rows.
I will have a picture up as soon as I finish the potholder I'm working on.
Meanwhile, check out this free pattern from KnittingHelp Hot Pad
It shows what each side will look like when it's finished.