I use oils.
There is a post on my blog about them but I will summarise here..
I use the following for the following reasons:
olive oil: shine giver.
coconut oil: strengthens my hair.
castor oil mixed with any oil: i am sure this makes my hair grow more although many have said it doesn't, it works for me because I have done tests so hey.
i put them on for about an hour and then wash it out, sometimes i find it hard to wash the oil out so i do think you should use a clarifying shampoo as these are good at getting the oils out.