Never heard Aajonus speak about it.

But going by experience & guess I would say use butter. But personally I would eat my fats instead.

Eat lots of raw unsalted butter and daily lubrication formulas(they reach the skin better).

Or like I do myself, just limit your sun exposure in the beginning and work it up over a couple of days. If you're really white start with 15 minutes daily, then every 2nd or 3rd day increase by 5 min.

I'm naturally inclined to tan easy despite being a Scandinavian white guy, but I start my tanning exposure already in the spring when the sun starts showing. Helps a lot to build before the "real summer" begins :)

Good luck!