You can start off by being realistic and finding an actual pretty hot or cute person with a high chance of finding dating success. Start off with something easy. I'm not someone dating coaches should seriously consider coaching to begin with. I wasn't very satisfied yet to start looking for dates seriously and distracted with finding personal answers. I'm now living my life to fulfill these answers. Basically, it's a given that a guy being short generally gives him a harder time with finding someone to date. I can't respect a dating coach who can't address this aspect and this friend failed to live up to it.
The friend is trying to coach another friend who is a girl to find a long-term relationship. I'm not sure if it's occurred to her that maybe the type her friend is dating is the reason for short term relationships. Maybe she should try out something fresh. Also appearances wouldn't matter in the long term when it comes to making daily decisions with a partner anyway. If a handsome guy or beautiful lady you are dating cheats, do the looks still matter with retaining your trust? Why be so close-minded to begin with?
This is all starting to make sense.