This year my oldest was in Year 4 and working fairly independently. Because in Year 4 the AO schedule has a more complicated reading schedule than in the past, I had to modify our schedule to accommodate that, and I had to find a system that let my dd work independently while making sure she completed her work well.
We still used the chart format schedules (new, up-to-date versions soon to be available on the AmblesideOnline website). I edited the chart to reflect the additional work I wanted us to be sure to get done and also to reflect our choices when more than one option was provided. I added checkboxes to items that must occur more than once a week. I then organized the various rows of once-a-week work into categories, each category containing approximately four or five assignments. The categories were chosen to group work of similar difficulty together. Each day, dd must do all the daily items, plus one from each category. That way, by the end of the week all the assignments would be complete, and each day would have assignments of various difficulties.
This sounds slightly complicated, but it really wasn't hard. I put the really hard readings in one category, the easier readings in one category, the books with assignments (like experiments) in one category, and so on.
I printed the schedule for each term using my printer's option to print up to four pages on a single sheet of paper as a booklet. That meant that each term's schedule fit on a single sheet of paper. To begin the year, I had my dd report to me as she finished each assignment, and I checked them off in my app on my iTouch. I think next year I will actually keep my own copy of the full schedule and mark it off as each item is completed, at least at the first of the year, so we can make sure we are staying on track and not skipping anything.