Any length(can cut later) 1/2 pvc pipe
Heat gun or blow dryer
I went to Crafty Beaver and I got a 1/2 inch PVC pipe that was about 4 ft. It only costed like $1.
You have to then get a picture of what the handlebars look like maybe online so you know what you want it to be. You have to figure out how your hands will be on it and then make a mark where your hand fits right. Then you have to get a heat gun(or blow dryer) and heat it up right below and on the black line and then fold it down as shown in the picture. After, start going down the folded piece and bend it to your desired shape.(Note: Doing a little at a time going section by section works best so that the PVC just doesn't totally fold in.)
Once you have it curved all the way it should look a little like this:
You then have to measure how long you want the handlebars to be on you bike and then you figure out how your handles will be one the other side. You can easily cut off extra pieces.((Sorry, the pic shows me cutting the handle but you can do that also if it's too long.
Then you have to do the heating and bending to the handlebar just like you did to the first one. The ones below aren't perfect but they should look a little like this.( If the PVC starts to fold you can press it against a table or something to make it flatter.