I can tell by your question that you already know what you supposed to do. Yes you should DT with heat. The heat opens the hair shaft for the conditioner to get in.

The rest of it is trial and error. Keep up the good work.
3A, Protein Senitive, Low Porosity,
Wash: Suave Naturals Conds (excluding Coconut), CVSB
Rinse out/Leave In: GVP Cond. Balm, KCKT,
Style: Naturelle Gel(winter HG), KCCC (summer HG), Flaxseed gel
Love your hair: Love yourself!