Do what everyone else does.
There you go, the guide is over. If you want to live a mediocre life just follow the herd.
- Don't speak up
- Don't question the status-quo
- Don't try anything new
- Don't help others
- Don't create
- Don't live a meaningful life
If you want to be mediocre simply look at what is expected and do the same.
Graduate from some college, it doesn't really matter which. Find a job in a field that has been around for decades, but don't get crazy with some new technology, choose something which has a history of mediocrity. Go to work, sit in meetings, stare at a screen, say yes when your boss speaks, and go to company happy hours.
Once home, watch Netflix and look for a popular show, you don't want to be out of the loop. Watch it, even if you don't like it or it offends your ideas of morality. Eat a plain meal and get ready for a weekend of drinking and having the same conversation you had last week.
When you do the above you will have a nice mediocre life. You should eventually work your way up to mid-management and be set for life to continually do the same thing every day.
It's really that simple.