I was once driving with friends in the car and needed to fill up on gas. As we were getting close to the gas station, my friends tried to pressure me to ask the attendant something odd instead of the usual, “Fill regular, please.” They decided I should say, “Fill decaf!”
I absolutely refused.
I was so focused on not listening to my friends advice, that as I rolled down my window, the words that popped out of my mouth were, “Fill decaf, please!”
In Novorodok, there was a practice to do things like this intentionally. The common example was to go into a pharmacy and ask for nails. (In a time where pharmacies actually only sold medicine…)
Rav Yehuda Leib Nekritz explained the reason for this behavior was to train yourself to have courage in any situation. Once you can make a foolish request intentionally, you start being able to stand up for what’s right even when you feel foolish. This wasn’t something they did everyday, rather just occasionally so they would have the courage “in their back pocket” for when it was needed.
The same goes for practicing bitachon. Once you start and get a little experience with smaller things, you know that you have the ability to have bitachon when bigger things arrive. It’s already in your pocket.