I call it "seeding." When a mess is bothering me but there's a barrier (internal or external) to dealing with it completely in the moment, I "seed" the cleaning process by doing just a little bit.
A few rounds of seeding can have a surprisingly big impact and every round is an opportunity for the momentum to kick in it that leads to the whole job getting done.
It's remarkably easy to get into a good flow doing this starting from a pen here or there and eventually cleaning whole rooms.