Hotkey for `%<>%` addins not working

I use the compound pipe from magrittr for df%<>%funs() instead of df<-funs(df) all the time. I'd like to make a hotkey for inserting %<>% the way you do with a one-sided pipe but I haven't been able to figure out how to add my own symbols into the addins menu to then assign a hotkey. Can anyone explain the process of adding your own shortcut into the addins, preferably for Windows?