Well, according to Super Smash Bros., Ness wears his hat sideways. If you look at Ninten's character art, you can see that he wears it with the bill facing left.
*insert comment about people should be able to wear whatever they want however they want without being judged*
- "oh, this isn't about a girl in skimpy clothing though, nevermind I guess. Proceed"
- "oh, this isn't about a girl in skimpy clothing though, nevermind I guess. Proceed"