Start with about 15 drops for a 2 oz bottle or jar, and adjust from there. I think I used about 25 drops of the Seraglio, but I wanted it fairly strong. Also, you can actually melt the shea butter lotion, mix the scent in, then pour into your container. When it cools it re-solidifies. I put it in the microwave for 15 or 20 seconds, stirring each time, until it was fairly liquid. Didn't seem to hurt it a bit.

 

Apparently, adding oil to inexpensive Walmart unscented lotion works really well too. You don't have to buy the quantities that I did, pay for shipping, etc.

Source: Lotion, oils, butters, massage bars, and anything else