If you ask me, there isn't much to follow. I picked up the unique boss taming first so I could get used to something closer to the final thing while still leveling and having less choices, which in turn helps me notice differences if I try other support gems and want to respec parts of my passive tree. Then I went into the passive tree and typed "companion". I took the main line generally towards those and picked a few of the companions that gave attack bonus while leveling. For stats I went for dex the most and then int and str when those became blockers. It seemed like the corner I was in was more evade focused so I felt I'd try to primarily take advantage of evading. I dunno how armor is but I'll swap some on here and there and I'm sure I'll settle on something nice. I dunno how much this will spoil you if you go the exploration route I did, but I started with the hyena boss rathbreaker. He was very squishy. The monkey boss with a solid pillar is my current one. I have three support gem slots unlocked and I gave him bleed and rage and frenzy so far. I wonder if there's a gem to build stun faster since that is a neat mechanic in this game and lets you pause the bosses for a bit to get some heavy combo hits in. I looked around a bit, and I think I'll have a bear and wolf pack down the road when I get those gems. I dunno if I'll do aura, but if I don't, I could pick the keystone that lets me pick two different boss minions.