Bridge thought

So I have been watching the video of Rachel in the Study Q and A. Rachel talks about bridging thoughts if you don’t yet believe your new thought. If I can’t seem to believe my thought, do I change it /use an add on, and practice that for the rest of the month? I really want to move forward and believe my new thought. I am feeling frustrated. My thought is ‘I have as much time as I need’. I am trying to let go of overwhelm.

Or do you use a bridge thought for a couple of days and gradually progress up the ‘ladder’?

Thank you xx