Hi, Here's a thread which i used.
http://www.xt660.com/showthread.php?t=18695

Remember to fill it in stages (as per thread) and warm the engine before checking the levels. Check the level in the upright position, take out the dipstick and place it back without screwing it back in.
Hope this helps. Not sure about the 10/30 oil i'm sure someone will be along to advise.