A lot of it depends on the level of competition you are looking at getting into. Some women are running some serious gear which results in serious sides that they either deal with or use other methods to keep it under control or disguise the issues. Also another factor would be what experience with PED's do you have if any.
If you are completely new to PED's a good springboard is a simple Anavar stack. Since you are looking at going fairly hardcore in the future you could start with 5 mg two times a day spaced out at about 12 hours apart. Since you probably already have your diet in check if you're looking at competing you should see some relatively decent results from this simple introduction. Once you run your first cycle for about 8 weeks make sure you're not having any side effects and your next cycle you can start to up your doses. One thing with Anavar is make sure you get an at home test kit to make sure you are taking legit Anavar.
As you start navigating the world of PED's you can also start looking into Primo, winstrol, and a slew of others. If you are post menopausal you should get your blood work done and make sure they check testosterone levels. A lot of women that are post menopausal will have low testosterone levels and testosterone replacement therapy is an option that has amazing results for these women, but doctors really shy away from this treatment and prefer to treat with estrogen therapy which is a little more tricky cause they have to get all your hormones to balance out. My wife did the TRT and it worked great. She decided to see if she could get it through the doctors though, so right now they are playing with estrogen creams to try and balance her out and it has been a major pain as they try different levels and then have to deal with the compounding pharmacies. She is probably going to get back on the low does TRT here soon unless some break through occurs.