How you do one thing is how you do everything. The source you draw from when you exercise displine by showing up to the gym, making your bed or organising your day is the same source you draw from when you need to exercise discipline as a trader.
If you can't even show up to the gym to work on your health consistently, how the fuck are you going to maintain the processes essential in a trading business?
Don't try to become a more disciplined trader - instead become a more disciplined person.