It's best to apply u're concealer after u're foundation, if u apply it before u tend to "wipe" it off and smudge it when u're applying u're foundation! Concealer brushes are fantastic for covering-up blemishes..
Dust with loose powder last..
Agree, the ever so camp MAC make up artist in Harrods told me the same, and he was well fit, so he must have been telling the truth innit!