As Fleecewife says, the most important thing is to KNOW you are going to get them tipped up, whatever breed they are.
I can tip a Swale more easily than a large Texel - the biggest Texels are so large I can't reach both ends at once. If I think I may not be able to tip a one, I get BH to do her - NEVER let them learn they can beat you, they have to KNOW you'll do it too!
Practise on lambs, if you can - even though they're small enough you can pick them up and plonk them on their bottoms, do it the folding-head-in way so that your body learns the moves.
It does get easier, it really does - but some of it is developing the muscles and muscle-memory, so don't be disheartened if it takes a while to get the hang of it.