Step 1: Raid the office supply room
Though if I were you I'd grab a handful of those fancy, expensive pens while at it...
Step 2: Arrange the clips
Step 3: Slap it all together
With your flower-looking shape laid-out and ready, take two rubberbands (two is always better then one...) and stretch them out between four fingers, as shown. You want to make sure to stretch them out larger then the circumference of the clips. This will allow you to drop them down, over the black clips in one smooth motion. You want to be able to quickly release the rubberbands so they contact the clips at once - other wise your shape will not stay in tact.
Now carefully flip it. Take the remaining two rubberbands and reinforce this side as well.