One of my tools is a never- ending to-do list (pen&paper). It's a substitute for having a memory, it's always on me and I have to write things down as soon as I realise it's a task I need to complete. Ticking items off helps me stay motivated, so if it's a longer process I'll break it down to get more ticks (eg think about x, outline plan for x, spend 1 hr on x).
Then on a given day I can make a separate list of things I need to get done that day and stretch goals, with the must- haves split into hard and easy columns (based on how they feel to me, psychologically). Ideally I try to start with the hardest thing first, then reward myself with an easy one, and repeat.