Career-conscious ear stretching?

Hi I'm currently in the beginning of stretching my ear lobes. I don't want to go too far for fear of my lobes getting really saggy (and unappealing to potential future employers for middle-cl jobs). What's the largest size that won't bend my ears completely out of shape? -- i.e. there can still be small visible holes after the lobes have been empty for months but not so big you can stick your finger through or anything like that...