Not so much a guide per say and the walk through will do a much better job but a quick overview of this achievement is that you need to get to level 36 to unlock this achievement.
You need 109 points if in a single tree, 110 in a dual tree and 111 in a 3 skill build. Breakdown below:
Archmage - 109 Sorcery
Warlord - 109 Might
Nightblade - 109 Finesse
Champion - Might 55 & 55 Sorcery
Blademaster - Might 55 & 55 Finesse
Shadowcaster - Sorcery 55 & 55 Finesse
Universalist - Might 37, Sorcery 37 & Finesse 37
If you've not focused on any trees or got your points spread evenly you can use a fatewesver to redistribute your points.
I played on Hard and finished at level 34 doing a few side missions and the faction storylines. To speed up leveling up at the end I kept filling my fate meter and then travelling around the final area, amassing a following of enemies and then unleashing. This gave me between 8 - 10k of experience each time depending on the group size.
Hope this helps and if not let me know how to improve.