You obviously need to do a lot more research before you start breeding them. You should know these things! She needs to be ovulating... or they won't breed. Gravid is basically another word for pregnant.
I think what the others are trying to say is that the questions you are asking are very simple.
If you dont know the answers to these questions without posting a thread, we highly recommend NOT putting your geckos together just yet.
Breeding isnt an easy hobby, and takes a lot of research, time and money.
I would recommend searching these threads (the search function is very very handy) and read, read, read.
Once youve done enough reading, you will know the answers to these questions and may be able to determine if breeding is something for you.
There are a lot of hard questions you will have to ask yourself, breeding isnt always fun and easy.
I would also try to avoid holding your gecko by its tail unless she has something to support her front half on. Its very stressful for them to hang by their tails.
That picture absolutely horrified me. I don't think you should be even thinking about breeding if you don't even know the basics such as properly handling a gecko.