Buy a golem. Pre-Patch are better cause they don't take damage but are expensive and hard to tell if they are really pre-patch. Buy yourself a 100% posion damage weapon without any hitspell on it for the type of weaponskill you want to train. Or a 100% posion UBWS weapon would work as well for any weapon skill but archery.
Make sure the weapon is as fast as possible get a dynimo's helm arti if you can as well to speed up your SSI. Then tell the golem to guard you, then tell it to attack you, then tell it to stop. If you did it all right it should just stand there and let you wack at it and get your gains. If you did it wrong you'll probably end up Luna roadkill if that happens just keep trying eventually it will stand there like a dumb golem should.
If your under 70 skill in any skill your trying to raise you need to use a NON-GM made golem if your over 70 in the skills your trying to raise you must use a GM made golem.
You can train magery and lumberjacking using this method as well. For magery you need a 100% posion mage weapon, for lumberjacking a 100% posion axe.
Thanks pretty much it. Hope that helps. Good Luck!