Which is the safest way to remove ticks?

Hello everyone,

I've checked the archive but couldn't find anything referring to the ticks problem. It's summer now, and just today our 7-month-old female JRT got three! Which is the best way to remove them? No matter how carefully we try to do it, two or three times their heads remained in the wound. How dangerous is it, and should we see the vet about it (I believe we should)?
Thank you so much,