record/video and watch yourself is the best one above.
That and the friend listening to comments.
otherwise you dun gotta have a strong ego to invite comment. Because opinions are like arseholes, everyone has one. And they may crap on some deliberate artistic fillip you sweated over.
And if you are going to be swayed by one person it is a narrow slippery slope you are on.
A range of comments at a song-writers' forum is useful, providing there are several comments.
Personally I prefer the "if you tried xxx" kind of kind comment.

At the end of the day - be yourself.