Have a look at this explanation: Slap bass - #34 by kristine
Also - I get sooo stuck when I try to slap through. I think you should feel free to start with your own technique.
And, I only tried “Thumb through”+“teeter totter” for like twenty seconds - but to me it seems you need to pay attention to how you lift the hand on the pop. Think of where the back/outside of the hand points after you pop the string up: does it point to the floor, or towards your body? What feels better to you? What’s more movements in total, so after you return to a thumb? Go slow, pick one and see if you can do the exercises.
Cheers,
Antonio
PS: I’m not a slapologist, so please take this as good natured advice by a fellow beginner. 