Quickly assign tags
Tags can be assigned to transactions by:
typing the tag's name into the corresponding text field in the details panel
using shortcuts
To choose a shortcut for a tag
Select Squirrel > Preferences…
Select the "Tags" tab.
Select the desired tag.
Click on the "Click to set shortcut" button.
Press any character key.
To assign a tag with a shortcut
Display the transaction's details panel.
Display the "Tags" pop over by clicking on the corresponding button, next to the "Tags" text field. Optionaly, you can make this pop over a floating panel by drag and dropping it to a different location.
Select the transactions you want to assign the tag to.
Press the key corresponding to the tag's shortcut.