meinus, my answer to the OP question would be "do a job like that yourself"
Not being flippant, but kids look at what you DO, not what you say.
I also wonder why you would like your daughters to consider these male dominated areas? Are they "better" as dominated by males?
I am sure I would not want my daughters to NOT consider a career as it's male dominated, but not sure I'd make a big deal of it.
Trying tot hunk what y parents did, they never talked much about gender and gender roles. My dad would have loved for me to be a female engineer, as he loves mechanical engineering and wanted me to understand the fascination.
Despite that, I chose arts. Ended up in a male dominated area in the end by getting into IT though. I remember being at conferences with about 99% men. I remember it being an advantage, as people remembered me more easily. Never felt like it was a big deal though as I always grew up with brothers, had male friends throughout life, and never felt that gender was a big issue.
But things have changed, haven't they? At the time, in the 70s and 80s I thought it was the beginning of total equality between men and women, but somehow we landed here, in 2014, with little girls dreaming of being princesses. Weird really, never saw that coming!
But to answer your question: lead by example, and don't make a big deal about gender.