You may laugh but im being genuine

A few ways

1) any task that is dead boring and repetitive for a couple of days.

2) any task that physically requires hard physical work that is draining for at least a couple of days

3) any intelligent task that has false horizons and you think your done but your not.

We are too used to comfort and ease IMO in the developed world. We may not need persistence everyday, but in my life, damn it's reassuring to know I have it. If you can do the above especially 1+2 without a vision etc to inspire you then I believe you can do anything.