Have you read through a dozen or so existing ODST build threads? That's the best advice: Learn from other people's successess and failures. Here's mine but there are so many more here. One Saturday spend reading will probably sav you a month of waste.
Planning So I decided to go ahead and build an ODST cosplay. In hind sight I know now I should have done it before my Spartan - just because the loose tolerances, visible straps, military surplus pouches and 21st century military inspired look make it a better choice before the more exacting...
www.405th.com
Also... A day or weekend spent tuning up your printer and settings so the parts aren't coming off like this will pay you back 10x in human labor having to clean up all this rough printing, what looks like under extrusion (or maybe excessive retraction), and other issues. I'd much rather have the printer take twice as long while I'm sleeping or mowing the lawn if it saves me countless labor hours.