I guess my case is different because we have multiplication songs in Cantonese. (Not really a song, just multiplication facts.) It takes like 30 seconds to read a full column, and kids were taught to read aloud a column at a time. So just plain old repetition, but easy to catch on after a while. A few short practices everyday in a week would be 15-20 repetitions on a single column, which is a fairly good starting point, and very short practices would minimise mental burdens.