Male or female, we all want to put on size and get ripped! Its a 2 step process though. A, we need to eat enough food to grow new muscle, while not getting overly fat in the process and B, reduce cals in such a way that we can lose fat while maintaining the muscle we gained in phase A. Sounds easy on paper, right haha! Clen will mainly help with fat loss. The main way I would use it in the off season, is to spend some time growing, and then, if needed, do a short, 4 wk "mini cut" to shave off unwanted fat...then back to growing. I want to stress "if needed". If you can maintain a fairly lean physique while growing, then there is no need to do the mini cut. Remember, when you are cutting fat, you are slowing muscle gain. Ideally, your off season would be a continual progression, growing right up to the point that you are ready to cut. 

If you did a mini cut and used the clen for 4 wks, I would take 40mcg for the first wk, then add 20mcg each wk, as tollerated. Then after 4 wks, come back off and readjust your diet for mass gains. 

As for other options, it all depends on how serious you are. Anavar at 5mg for 6-8 wks at a time, is great for muscle gain, but it is an anabolic steroid and can come with side effects of taking male hormones. It's the safest of all the steroids, for females, but you'd still want to do a lot of research on it before jumping is. See if it's worth the risks to you. Also a low dose of GH would be good. It'll help with fat loss as well as help build muscle. The drawback is, it is a long term commitment. You'd want to use 1-2iu for at least 5 months to see an effect and even then, just like anything else, your results will be very dependent on your overall diet and training plan. If you go with var, I'd suggest Geneza. If you go with GH, I'd suggest Hyge. You can also combine GH and var without adding additional side effects