I like Krik's response too.
I am not familiar with the book, but I would suggest using an anchor, such as bringing attention back to your hands (or breath), each time you find you are feeling under pressure or have simply forgotten to practice. It will become stronger and easier overtime, try to enjoy doing it now
rather than considering how much time it will take to get better or how often you have forgotten today (these are just thoughts and not practice which is your goal). The path is the goal, keep treading it
Just keep bringing your attention back to the same location and that will help improve awareness of other factors too e.g. the room, the light, your ideas shouting for attention, people, the job at hand. It will pay-off.