Its taken me years to finally master caulking, and the solution was in my hand all along -lol...
First off, I tape off the area to be caulked (doesn’t have to be perfect).
Second, I use Dicor ‘self-leveling’ caulk where there may me a little flexing (like around the side wings, etc) because I found that it remains slightly plyable and doesn’t get so hard to develop crack lines during body flexing and over the loooong term.
Thirdly, apply only a small bead (as in the OP’s picture).
Fourthly, move FAST.
And lastly (this is critical to a ‘factory like’ caulk line), chase with mineral spirits or paint thinner - but here’s the secret ...
MS on on only the index finger will work only for 3-4” until the caulk then begins to gum up and look like h@ll - your frustration will be off the charts... Sooooo, dip all four fingers into the MS, then spread them far apart and then chase the caulk line in one bold stroke using all four spread wide fingers, and go as far as you can until you need to re-wet your finger tips, then continue on...
After reading about far too many failed caulking techniques, and having success with none, this home-brew method produces ‘true’ factory like caulk lines with little practice...