Using a Circle cutter - or you could even use a bowl to trace out the circles if you don't have a handy circle cutter. I cut the holes 5 inches diameter. If you are using scissors, then the easiest way to cut the circles out is to start by poking a hole in the middle of the circle and then use that to cut out to the circle.

With five inch circles, you can fit three circles on the width of the poster board. I cut out 24 holes, but feel free to add as many or as few as you would like. I was happy to have 24, so that all 11 kids got to go twice and a few a third time.

Once the circles have been cut, its time to cut the tissue paper. Because I was doing a rainbow, grab a rainbow variety of color paper while you are buying your party supplies.Each Tissue square was approximately 6 inches.

Next, you grab your prizes.  When picking out the pinata fillers is that you need small items that do not have a lot of weight to them. They will be held up in a paper bag and so heavy items are not great for this pinata.

Place one or two prizes in each circle.

The next step is to grab your brown bags. I cut the bags down to approximately 3 inches high. The top portion of the bag can be reused as a snack baggie. Simply staple the bottoms or tape one end together.

The trick to attaching the bags to the poster board is to cut each corner of the bag down approximately an inch on each side. Then fold each end of the bag back. 

Tape each of these flaps to the back of the poster board that are covering the prizes.

Grab your rope and cut it to approximately three to four feet. Punch a hole with your scissors or with a hole punch at the top of the pinata between the second and third hole on both sides. Tie knots in each end of the rope to those holes. This will be what holds your pinata up on the wall.