From the looks of things you haven't sacrificed any stats. As you sacrifice size you unlock the skill tiers, with the amount needed for the tier shown next to the yellow line. Keep in mind that while you are sacrificing your size, thus making yourself weaker, it also takes equivalent exp and levels you down so you can get it back without too much trouble, especially at lower levels. You look to be decently far in but my personal strategy is to get a follower or two, sacrifice all size, find a dungeon you feel like running through for a while, and grow and sacrifice after every fight. Anyways, to reiterate that answer to your question, you should just need to sacrifice. One last tip as well, if you ever want to grind sp just do what I said above with size specifically. You get sp real quick.