a few tips
Performers particularly at singers clubs could improve if they practised by listening to themselves, checking diction and intonation, getting a note to know where they pitch, watching oneself in a mirror is a good idea, one can see oneslf as othere see ones performance, then take a deep breath before performing.practise singing from the diaphragm to get good breath control, practise singing long notes and arpeggios and try and regard paper prompt notes as a stabiliser which can eventually be discarded, if you have to sing from paper bloddy well practise with the paper notes