I now use the finger tip method and I think it works better. This means your index finger is the measuring scoop. You need to coat the tip, anything that drips off is not needed. You then spread the coconut oil between both palms and apply to your hair. Ideally section your hair into at least 4 sections and just use your palms to spread the coconut oil onto your hair. Check that your hands are not oily, if they are, continue to apply to the next section (don't get another finger tip!).
Usually 2-3 finger tips are sufficient for the entire head. With shorter hair (under 6 inches), 1 finger tip is enough for the whole head. Focus on spreading the product well and ensuring the hair has a very thin near invisible coating.
If your hair feels greasy, you have used too much and with coconut oil, this is easy to do. The remedy for this is to wash your hair. In fact, you probably should just sit for an hour or so to treat it as an oil treatment, then go ahead and shampoo/condition your hair (Then you can claim the oil treatment was just part of the plan :)).
Edit to add - If you still have no success with it as moisturiser, just add a teaspoon to your hair conditioner instead!