DIY lenscoat
I made this lenscoat for my 70-200mm telephoto lens. I need an external protection for this heavy+long lens since I always accidentally bump the lens front/hood on my car door, wall, etc. Besides, it's a nice cosmetic compared to the boring black colour. As a hobbyist, it suits me but if you're an event/formal photographer, you will look weird with this setup...unless you like to be different from the others. 
It's pretty straight forward, measure, cut, stitch/glue, and within a couple of hours you're done! It took me almost a whole day to finish this since I sew 80% of them by hand (and my sewing skills are terrible ) and the rest I just glued them together using a super glue as my fingers were getting tired sewing non-stop.
materials for the coat; a camouflage pattern scarf, velcro and soft foam. I bought the camo scarf from an outdoor shop, and the rest are available in most tailor shop.
The "naked" lens w/o tripod collar
Fitted with a camo lenscoat
Coated parts: lens hood, focus ring, zoom ring and tripod collar mount. The Sigma 70-200mm HSM II for Nikon doesn't have any switches on its body and the AF can be manually override by simply rotating the focus ring. Covering both rings, (focus & zoom) won't be a trouble for me.
The tripod collar is removed and the mount is covered
with the camo pattern background