HIPS prep and painting questions:

[Wicker]

I'm trimming my front and back armor and will be ready to prep and paint soon. Any of you experienced folks have any tips on prepping the surface for paint? I've never worked with this sort of plastic before.

[Blackwatch]

wash it with soap and water and let it dry to get rid of any hand oils.
I would prime it with black primer. my favorite black primer is Rustoleum American Accents 2X black primer. its a bit harder to find , but it is out there. You will find this in real hardware stores, not box stores or walmart.

If you are unable to find the black primer, you can use Rustoleum Canyon Black , again in the 2x line. A couple of light coats is all you need. Then apply gloss black.

I would suggest stickign with the 2x, but you CAN use Valspar gloss black as well over the top of the Rustoleum paint.
check my Rubies helmet build tutorial for more paint info.

Best advice---this is not a one afternoon job. I would apply these coats and let them dry for a couple of days to completly cure out. I would apply the gloss in VERY thin layers, building up the shine, following the directlions very closely regarding flash and reapplication times.