Speaking on British TV show 'Lorraine' show, Sinead said: "I always say to my kids the only purpose God put you on earth for is to be you 100 percent. To be who you are, that's success.
"Sometimes that means you may not have fame or a good name or money or stuff but that's not necessarily success, do you know what I mean? It's really can you be yourself and be true to your contract."
Sinead, 42, cancelled a tour last year due to her bipolar disorder - urging fans at the time to recommend a psychiatrist in her hometown of Dublin, Ireland, to save her from "serious danger" - but is now back on track with her new album 'How About I Be Me (And You Be You)?'.
She added: "I think I'm having a great time making music, I'm really enjoying that the live shows are going so well.
"Everyone's responded so well to the album and everything so I'm really glad the kind of focus is back on being a musician. So long as I just keep my mouth shut and behave myself ..."
Sinead follows her own advice, as the tattooed musician credits her success to being herself and consulting the "Holy Spirit" when making decisions.
The singer - who was once ordained as a priest by an Independent Catholic group - explained: "To me success is really can you be yourself. You're working in an area which can be very vampirical and spiritually slightly dodgy and can you get from one side of the board to the other is the way I see it.
"And still maintain the contract you made with the Holy Spirit before you got here and which you renew constantly along the line, which is basically just be yourself which is all I figure."