You have to make it easy to. Or put another way, you have to make it difficult to do the easy thing instead.
That could mean putting your kindle next to your toilet, so every time you need to go to the bathroom, you’re spending time reading something educational instead of scrolling on twitter.
That could mean making the one-time decision to delete YouTube from your phone, so you can’t use it as a crutch to fill the 5 minute gaps of boredom between meetings.
That could mean choosing a business partner who’s smarter than you, so you’re constantly playing catchup to learn as much as them.
That could mean taking 5 minutes at the end of your day to write down a prioritized to-do list you can attack the next morning.
That could mean removing the TV from your bedroom, so you aren’t tempted to sacrifice crucial sleep for instant gratification.
That could mean batching all your shallow work tasks (replying to emails, creating new sprint tickets, etc.) into a single time slot so they don’t interrupt your flow state.
That could mean ANYTHING which makes it as easy as possible to work as hard as possible.
Instead of wondering why you don’t feel motivated to do something difficult, ask yourself what's motivating you not to.
Then remove those things.