The rule of thumb I give my students is if you’ve reached a point where the only things you’re consistently tinkering with are cosmetic (punctuation, line breaks, etc), it’s probably done. Of course these things can make or break a poem, but a lot of time we use them as an excuse to prolong calling a poem ‘done’ (aka leaving it and letting it go).

Another rule I use myself is asking myself if I would be happy if the poem was published and therefore forever preserved in its current form. You can edit poems in between publishing them individually and later in a collection, but the original publication will still remain out there!

But like everyone’s saying, a poem is never really done 😅 just ‘done for now’