First- you need about 2 or 3 big cardboards (it's your choice what length you want it to be). It's very important that the cardboard would be thicker than normal so that it won't collapse.
Step 1: Work
Second- glue the peaces together to get a straight block of cardboard. Glue it very good, don't be greedy because it will pop out.
Third- bend the end's of the block the cardboard, but be CAREFUL it can rip or you can pop the glue out.
Fourth- mark the lines on the bar (I went retro), be creative as possible :)
Step 2: Paint
WARNING PAINT IT IN A WELL VENTILATED PLACE, outside is best, because I did it in doors and got poisoned a little bit... Okey so paint what color you love, like I said, be creative :)
Step 3: You're Done!!
I used it for party's and other occasions, it's not perfect, there are mistakes but you live and you learn, be safe and have fun!! :)