1) Download MCUpdater
2) Run it
3) Log in to your minecraft account
4) Hit OK on the message that a pack needs updating
5) Hit update in the bottom right corner (trust me it will never shut up if you don't)
6) Click the + in the green circle in the top left
7) Paste this http://okshard.okdedicated.com
(right click and save link since the board likes to mangle links) into the box and hit OK
8) Click on the new entry called "OK Shard" on the left.
9) Hit update in the bottom right corner
10) Wait for it to finish (launch button will unlock, you can watch it work on the progress tab too)
11) Click the gear on the top left
12) Bump up the min and max memory. I crashed a couple times while testing at the defaults. I tested it at 2G/4G and it seemed stable enough.
13) Click the launch button.
14) It no long autoconnects since that was the problem we were having with maps not persisting so login the old fashioned way and get to punching trees.