Installing a curved shower curtain rod into your bathroom is a good way to add a touch of class to the loo. Before you buy a curved shower rod, measure the distance between the two walls and extend the rod out so that it will fit properly.
Measure up both walls to the desired height -- typically the length of your shower curtains -- you want your shower rod to hang. Make a pencil mark on both walls at the height points. Measure from either the wall of the tub or the floor, just as long as the mark on both walls is at the same height.
Extend the measuring tape from the wall at the front of the tub or shower enclosure to the wall at the other end -- lengthwise -- of the shower enclosure. Mark down the measurement on a piece of paper.
Lay out the shower curtain rod on the floor.
Hook one end of the measuring tape onto one end of the rod and extend it straight across to the other end. The result will look something like a bow, with the measuring tape as the bowstring.
Extend the shower rod until the gap between one end and the other is the same distance between the two walls.