This isn't a "rule," but it's fairly common to see "somehow" used at the beginning or end of a sentence rather than in the middle... ... As the sentence is written now, no commas are necessary.

How do you use somehow in a sentence?

as a sentence adverb (making a comment on the whole sentence or clause): Somehow, I had the feeling that Jeff was going to be difficult. Somehow he managed to pass all his final exams. Farm animals are seen as somehow different from animals we keep as pets.

What is the meaning of word somehow?

: in one way or another not known or designated : by some means we'll manage somehow.