CD, I am sure not an expert on faux techniques but my best guess is that dry brushing is one of the few techniques that will work for you. To do this, base coat your walls with one color and let it dry. Then take your second color (usually the lighter one) and pour a small amount on something that is non-porous like a shallow baking pan. Use a brush that is no wider than 2" and very lightly dip just the tips of the bristles in the paint. Then wipe most of this back off on a clean rag or by brushing on a pad of paper. Now lightly flap the brush over the high spots on your wall. This will lighten the high spots of your walls and bring out the texture even more. How much paint you apply is up to you but less is better. You will have to experiment to see how much of the second color you want to apply, Remember that you can always add more color but it is a lot harder to remove it. Once you have decided on a color level for the second color, you will want to try to keep the same level as you go around the room.
Certainly, you will want to do a good job of the prep on the walls before you do any of this.