My bitch is on day 8 of her heat and she is starting to turn her tail and put her bum up for my male do you think it is time to put them together? Her season lasts for about 21 days, i was going to mate her on day 10/12/14 so will i mate her now or wait?

My girl starts this 'flirting' around this time too, but when presented to the stud dog she doesn't let him anywhere near.  She'll chase him around, tail flagging, try them together she could be ready!