A beautiful window dressing can really make a room. Hanging Sheer drapes under curtains is a beautiful effect. It allows light in but gives you some privacy. Measure your window to see what size curtains you will need and where you will want the curtain rod mounted. See EHow article 8550-How to Measure Your Window for Curtains. Mount the bracket for the double curtain rod using a power drill. Make sure that the placement is where you want it so that your curtains will hang correctly. If you are mounting the bracket in drywall, you may need to use anchors so that the weight of the curtains won't pull the bracket out. If you are mounting directly into a wood window frame you will not need them. Using the smaller of the two rods, hang the sheers. You will hang the rod on the inside bracket. Using the larger of the two rods, hang the curtains. This rod will go on the outside bracket. Add tie backs if desired.