Generally ADHD people have trouble with either starting or finishing a task (I imagine some unfortunate ones have both, which must be truly incapacitating). My problem is with the former, and to advance the most useful thing for me is the “smallest step” technique. I ask myself: “What is the smallest thing I can do to advance on my task?” and the answer is usually something I feel capable of doing. That means: step 1: locate the backpack; step 2: get out the right book and notes; step 3: take them to the least distracting place I can think of; step 4: open to the right page, etc. etc. Often the first few steps are by far the hardest, after which the rest flow easily and I won’t have to ask myself the question unless I get stuck or distracted.
Other helpful techniques for me:
– set a timer for 15 minutes and when it rings figure out if I’m doing what I’m supposed to be doing :),
– write every timed task on the calendar, even if it’s small and you are sure you’ll remember,
– write down before the assignment starts how you will know the assignment is completed (this stops me either from ignoring the last details or going deeply on a tangent),
– tell somebody to check with you at a specific time if a task is done, or even just state an intention out loud to somebody,
– try memorizing in motion (I basically walk around the room in circles and read out loud and then repeat to myself out loud what I have to remember — looks funny but it works),
– keep in mind what the ultimate goal is (teaching English to non-English speakers), and visualize how what you are learning will be applied to the task. (I tend to get resentful and close-minded when I feel “I must do” something, and this is a good way to get me to remember what I actually want out of a task),
– consider not taking notes. I cannot listen and write at the same time, plus my writing is nearly unintelligible when distracted, so I found it’s more useful for me to listen closely to the teacher and ask somebody for the notes (plus usually everything is online nowadays).
Good luck on your new endeavor! You are motivated to work at it, so half the hurdles are already passed.