I am currently bleeding my deore disc brakes, however it is taking forever for the mineral oil to go down. It is however slowly, I hope, filling with the stuff. Only problem is……how do I know when it is full and ready and how much oil from the shimano bottle should I expect to use in filling up the brake (it's the front brake).

Shimano says it bleeds up to 2 brakes so i'm guessing down to half the bottle. It helps if the previous mineral oil is a different colour because you'd know when the new colour oil comes through its finished.

You need to pump it thru whilst simultainiously opening and closing the bleed nipple at the caliper

Nice and short tutorial

http://www.5min.com/Video/How-to-bleed-a-Shimano-brake-system-66769651

Definitely take the pads out first so as to be certain not to get fluid on them. I think I used a stack of coins to hold the pistons apart.

I use a syringe and bleed from the bottom up.

2nd the above method, bottom up is the way to go, so simple and takes minutes per brake, it is idiot proof (don't try and prove that!)

Done now. Thanks for the help everyone.