Not difficult. Clean the surface with carb cleaner, grey primer, tape up the sights... barrel opening and any part you dont want to paint. Buy your preferred camo paint... 3 colors, no black. No black paint since those are the hard lines you are trying to get rid of. Walmart has the snakeskin netting in thier Crafts and Hobbies department for $.94 a yard (you can use lace patterns on a wife's gun!). Cut some netting and tightly wrap your Sig in it. 2 net layers and use different directions since snakes are always coiled or curved in movement. Your Sig will look and feel funny, if it does I promise you're doing it right.
I used OD green first. Let dry. Wrap it again, then paint angled strips on your Sig in tan. Let dry. Wrapped it again, then paint another set of angled stripes over your Sig with brown. Use a MATTE clear coat last. Remove tape. Set up your Sig on a pedestal, surround with candles, kneel down and begin to worship.