I'll be using the same base from the previous tutorial.
STEP 001
Add a new layer, set it's blending mode to overlay, and using airbrush, add a blush if you want, or if you want to bring out the cute vibes?
STEP 002
Set the newly added layer to linear burn and pick the colour of the lips and repaint the lips again to get a darker shade.
STEP 003
Add a layer and set it's blending mode to add. Now using any brush you like, make strokes like the above picture.
The final result! These are just the basics actually.
Comment if you have any doubts!