Be sure that the date in the upper right is showing and not the temperature (use lower right button to toggle btwn temp and date).
Then depress upper left button to enter set mode ( you'll see the seconds flashing). Keep depressing the lower left key as it will move the "flashing" mode from seconds to hrs, then mins, then months, then dates, and finally day-of-the week. Once here, while the day-of-the-week is flashing, use the lower right button to toggle to the day of the week you want. Then depress the upper left button again and your watch should stop flashing from adjmt mode back to real time mode.
If you know someone who is selling a ts-1200 in good order and/or know where to get replacement bands, pls reply. Thanks, Craig