At my work we have sticky notes in 5 different colors, if you want to change the color so it seems like you have 5 different sticky notes let me know. Plus it is a lot easier then what I’m about to tell you.
As for adding different sticky notes, duplicate the Particle Cell in the Project Pane or timeline. Hit F4 to open up the Particle Cell. At the bottom there is a Particle Source well. Drag a different sticky note into it and you have the new stickys on top of the old ones. Hit the Random Seed button to change things up. Click on the Emitter in the Timeline or project pane, check the 3D check box and then the interleave particles check box. Repeat for every new kind of sticky. Hope this helps.
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