Get a portable songwriting studio: a small digital four track, a compact rhyming dictionary, dictionary, and thesaurus.
Get the smallest Casio keyboard you can find.
Use a laptop if that’s your thing, but sometimes it’s fun to be without all of the options a computer provides.
And get lots of batteries.
Don’t do anything involving MIDI. Avoid having to configure anything.
Go somewhere where you’ve never written a song before — even if it’s as close as the couch in front of the TV, or outside in the back yard.
Just start up a drum pattern on the Casio and improvise against it. Record it. Overdub. Experiment.
You may not write any “keepers” this way, but it can be a fun creative exercise. It can also be stimulating to get away from your usual writing spot.