Hi! I use plain old Johnson's baby oil. It's just mineral oil and fragrance. (I have the travel size bottle and it lasts ages.)

Yes, you just put a few drops on very wet hair, from the ends working upward. I rinse most of my condish (but not all), get out of the shower, then put a dime more of condish in my palm and mix my drops of oil with that. (Just "thickens" it and makes it easier to distribute.). I smooth it over the nape section, then scrunch it into my ends and upward.

Then I add my stylers, etc!
2c/3a/3b, Fine/med, Dense, high porous, & normal elas.

Lo-poo - Renpure Keratin, SMR, Giovanni SaS
clarifying - mix Johnson's H2T with low poo
Co-wash - Suave Nats. clar. or coco.
RO - GVPCB, Ion Eff. Care, TN.
LI - SMR, Cure Care, or RO
Seal - MO or Jojoba
DT - + honey, ACV, & EVOO to SM masque & GVPCB
PT - Gelatin!, CNPF
Styling - FSG, AIF, BRHG, LALS/PS, GF curl spray gel, SM Souffle/Smoothie, LOOB
Oils - MO!, EVOO, jojoba, GSO, SM Elixer, EVCO, VO5 Hairdressing