Increasing Libido With Magick, Any ideas on ways in which this can be done? Options

I hope this is the right forum to post this...

So I've had problems with a low libido for a good few months now - I suspect it's because of the birth control pill, although I have been off it for a while now so I don't know whether it's just the lingering effects of the pill now or whether the cause is psychological. Anyway it's quite a hassle, since I used to have a very high sex drive, and it's putting strain on my relationship with my boyfriend (a relationship which is otherwise very good).

Lately I've been looking at magickal methods to increase libido, but I'm not quite sure how to go about it. I did do an invocation of Freya a few weeks ago, and even though I'm not too experienced with the whole invocation thing and I wasn't really sure if I was actually doing it right, it did have quite a positive effect on my libido. I'd like to try other things too though, just to get my sex drive back to how it was before. I've tried different herbs, namely ginkgo biloba, damiana, muira puama and ginseng. Haven't had much of an effect. I'm wondering - when using herbs , will they work better if they are somehow 'charged' with magickal energy? I recall reading something about this somewhere. If so, how would this be done?

Basically, I'm just looking for advice on different ways in which libido can be increased by magickal means. I also appreciate hearing from people with similar experiences or personal opinions on this!

Another idea is to tie three knots in a short cord at the new moon, reciting a suitable verse before sealing eack knot to increase your sex drive/libido, then sleep with it under your pillow and carry it for 28 days. Repeat if necessary as often as you like.
Works for most people, but not much for others.
I had to do this once in my mid-20's as I had a very sexually demanding girlfriend; but the truth was I wouldn't have needed it at all if she'd been my type and if I'd have fancied her; which to be frank, I didn't!