I have two small kids so usually I need my hand and I wear it with the strap while out shopping and what not. If I go out to eat or if I am out without the kids, I hold it my hand by the smaller handles.
I try to use the short handles although I always keep the long strap because I like being hands free. I saw one review where the stitches below the attachment of the long handles started to tear and that scared me! So I try to at least switch back and forth.