Build routines that make stopping more inconvenient than continuing.

Most people rely on wanting to continue, which fails on the days it matters. A better arrangement makes stopping the awkward option, whether that is because someone is expecting you, the equipment is already set out, or the session is booked and paid for. You are not fighting your reluctance so much as arranging things so reluctance is not the deciding factor.

Look at where you most often stop and add one small inconvenience to stopping. Arrange to meet someone, put the gear where you will trip over it, commit out loud. Design usually beats determination over a long stretch.