Just to be on the safe side, make sure both characters are just before an attribute level up. 7 with a level up waiting, or something like that.
Attribute glitch works because a character can't have 3 classes. So basically, you can only glitch the attributes up for a character with 2 classes.
So you could use a Soldier lvl3 to glitch up your Jedi0/Scoundrel3, or something like that.
Simply select the soldier, with the jedi right behind in the lineup, and do a FLU on the soldier by pressing Black then A really quick, so that the soldier's face shows up with the jedi's body on the level up screen.
Simple as that. You can now select the attribute you want, and also I do believe skills stick as well. If you're using the Malak's guide, you can do ANOTHER attribute levelup, but only if the character getting the attribute points really does have 4 level ups waiting for them. After you're done with the levelup(s), exit out of the menu screen, and go through a load screen. This will reset your characters' levels to normal, and the attribute points and skill points will still be there.