The correct informal ways to say, 'What's your name?' are "Comment t'appelles-tu ?" or "Comment tu t'appelles ?" More formal, for people you don't know, and for those who haven't given you permission yet to address them with "tu" and "toi", are "Comment est-ce que vous vous appelez ?" and "Comment vous appelez-vous ?".

Bonjour You can say ''Comment t'appelles-tu''? or ''Tu t'appelles comment? in French after interrogative words must be inversion, f. ex. ''Comment vous appelez-vous''? or we must use ''est-ce que'', but if iinterrogative words are in end of sentence we mustn't do inversion f. ex. ''Tu t'appelles comment? we say '' Où vas-tu?'', but ''tu vas où?''