When you start making something,
new ideas keep popping up as you go.
The solution to that :
have another go
four layers : two white, two yellow .... and a swirl
Also better photos (without the bottle !) of yesterday's vase
(not a very watertight one I confess, but you can put a glass one in it)
For this one I used only two layers of white
More experimenting will follow I guess ...