When it comes to practicing piano, we often think that "regularity" means practicing for 5 hours every day. You know, the "all of nothing" approach. Unfortunately, this usually means "nothing" and we end up feeling bad because we can't live up to what we imagine we should be doing.
Regularity, however, can mean a lot of different things. Here are a few of them:
Taking a walk with your coworkers during your lunch break on Mondays and Wednesdays
Eating a carb-free breakfast each morning
Doing 5 minutes of stretching exercises each day at some point
Listening to jazz in the car on the way home from work each weekday
Playing baseball in a recreation league each Spring
Practicing 5 minutes of scales at the start of each piano practice session
Taking a weekly piano lesson every Tuesday, even if you haven't practiced "enough"
Playing the same jazz standard each day for a month
Visiting a different major league baseball stadium each year, until you eventually get to them all
Learn a new Chopin Etude each year
Sightread through the Charlie Parker Omnibook every day for a full year
Memorize a new song each week
You get the idea. Now, the big question becomes "What are you going to decide to do on a regular basis?" What goal do you want to achieve?