I have this problem when Im trying to use tactile techniques to enter a dream I can't control the direction of the "motion"

For example I imagie myself in a hammock so Im supposed to feel motion going to the right then to the left then to right and continue like that.

But instead of feel what Im supposed to feel I feel as if I am moving diagonally and is very very VERY! annoying, because my mind is expecting roght to left movements but Im feeling diagonal movements so I start to get confused angry and loose focus.

Then I end up stopping the practice.

What shoud I do to feel the right motion?