Hello Brenda,
It is a good idea on how to maximize the use of Sticky Notes. In which there are task listed, and a check symbol is very ideal to mark the task that were done. Here the 2 methods:
Method A:
As for now, Sticky notes has no hotkeys for symbols. Example, in Microsoft Office word, the hotkey for the check symbol is 2713 + Alt + X.
The work around is to key in the code in Microsoft Office Word, and copy the resulting symbol to Sticky Notes:
But this is much easier (Method B):
In Sticky Notes, highlight the task that you've already done and press Ctrl + T. This will put line through the highlighted task:
Kind regards.