Nothing worse than being 20 hours into a game and find out, damn I really regret picking that perk or putting so much in to that particular stat, well help is at hand for those who have the PC version anyway. Although there is no respec mod available at the moment. The guide below will help you to respec without having to start up a new game or reload from some back dated save.
Please BACKUP your save games before proceeding in case you accidentally make a mistake.
Any changes made through the Console will disable achievements for that game instance.
Work around for the achievement problem is just to quick save after making changes and then restart the game.
Character Respec Guide
All the steps detailed below require the console which can be accessed on PC version using ~ key
Change character level back to desired level:
This will revert you back to level# with all base skills (adjusted for racial bonuses). You will keep your perks.
Remember to keep track of how many perks you have removed, so that you can re add the same amount. Wouldn't want to be cheating too bad would we.
player.removeperk [id] (this will only remove one level, so if it's a multiple level perk, do it multiple times, and always remove the top perk you've taken in the tree first)
To find out a perk's ID, use
help "perk name" 4
Once you've removed all of your perks, use:
player.advskill [skill] #
DO NOT USE player.setav name # reason being you will not level up! and prevent reaching max level!
Skill is the name shown in your skill window (without spaces, if applicable) except for Archery, which is marksman, and Speech, which is speechcraft. # doesn't refer to skill levels, but uses. So something like player.advskill lightarmor 50 means either 50 hits or 50 damage taken. With pickpocket, it means gold stolen. With alchemy, it means gold in crafted potions. You get the idea.
Use that command until your new skills are at a desirable level. Once that's done, you can level up normally.
Quick Perk Respec Only:
The above is a full respec. If you just want to re-assign perks use: