How much oil do you apply? {Your Opinion}

I didn't know what to write for today so I thought I'll pose a question to you all today. The premise of this question is something which I shall reveal in the following week but this question has nagged me to no ends since long.

How much oil should be applied? And, where should the oil be applied? How long should the oil be kept? Should you cover it with a shower cap or not? And, also, how should one go about applying oil or massaging the scalp? I searched on this topic and I found out that some people apply oil only to the hair length!!! Well, oil has to be applied to the roots and massage din so that it reaches the hair follicles and nourish it.

For my part, I don't have any answers yet. And, I am confused on all accounts. So, hoping that you would solve my confusion ;) Adios!!!

PS: Do you watch Vampire Diaries? I am not, in general, a fan of VD but this season is undoubtedly the best and I am in love Klaus :)