Keep a master calendar on your cell phone; enter even little things, like laying out your things for the next day or when you want to go to the gym, or when you regularly shop, or when you want to follow up on something.
That way, even if you choose not to do it, it is an aware choice you are making as opposed to forgetting and then feeling angry with yourself. That anger and so many of those regrets are harmful to us because every thought we have is a neurofunction and creates a chemical in our brain and body.
Once we have made the entry we can give that little satisfaction that tells our amygdala that we are doing something that keeps us on track, our brain will increase the dopamine again and will help us repeat that action again.
It may need an attitude adjustment to make it a pleasant experience: we do have a choice of which feeling we attach to a thought.
If you want to know how that works, book a session with me.