Stategies for teaching when the primary goal is to hold interest?

I am casually teaching some friends and family members how to program, but I wanted to leave this question more broad.

I feel as if most traditional courses give little thought to making courses interesting, luckily, those courses have grades and potential wasted tuition money looming over you so they hold your attention for ransom. Me teaching something casually does not have this benefit, so I have to rely more on making what I teach interesting, how do I do this?