I instigated it in my relationship (Although to be fair there is a valid point to be made - chastity and submission are not synonymous. You cannot force someone to become submissive by enforcing chastity and likewise, you can have femdom relationships w/o chastityy, so it makes sense that males usually initiate) Anyway, I initiated it, he was on board and we grew massively from there.
I got into it because it was an extention on a kink I already had; tease and denial. (w/o a device). I got into it because we had a D/s dynamic and it was a natural progression in our play style. Most importantly, I got into it because it turned us both on.
Again I would like to reiterate that you cannot slap a chastity device on a partner and expect them to submit to you and be worshipping at your heel. It has to be consensual and he has to at least have some element of desire along those lines. I know you can go onto Google and read "Make your man do anything you want - put him in chastity" or "Stop your man cheating - with chastity" or "Get what you want in the bedroom - chastity"....you get the picture, but if this is not your mans desire, you cannot proceed. All that it will cause is resentment, upset and issues. (and a bad break-up - possibly with a restraining order involved lol)
It is also important to remember that each couples dynamic is different. Just like "vanilla" (hate that term) sex, chastity play has a wide variety of different play styles and again, you and your partner want to be on the same page. If one of you desires tease and denial with reasonably regular releases, its going to be disheartening and no fun to discover his keyholder wants him locked 24/7 and not getting any release.
What turns me on is knowing he is constantly aroused for me and also having power and control. Knowing he is placing a high level of trust in my hands etc. It turns me on the make him beg, or grovel and see how far I can take him (In pleasure and frustration) It turns him on too ofc.
Chastity is powerful. It can be enforced without a device (If you trust him and he is committed to remain chaste until permitted otherwise) It can cause heightened emotions and I even notice a personality change from when he is in and out of chastity. You have to keep communicating always and he must always feel comfortable speaking up, with any issues or concerns.
I recommend starting slow. As mentioned, it can cause powerful emotions and even guys who crave this can find they jumped too far too soon, letting their fantasy outweigh reality and they have a bad experience. (again, keep talking) You can enjoy this kink without a device. (we did for years)
As for starting out, it very much depends on your dynamic and what works for you both. Just avoid jumping straight into the deep end and talk about things after, so that you can build up an idea of each others limits, desires and turn-offs. I dunno if it helps, but I wrote a guide on my blog, for beginners. It would save me re-typing all the info:
http://thegrittywoman.com/beginners-guide-chastity-orgasm-denial/
If you do decide to get a device, read reviews and do research into fitting and how to get started. I recommend not enforcing that he wear it constantly from the get-go, as it takes a while to get used to. You could start with just evenings, then maybe build up to days. Night time is the worst (nocturnal erections can be painful inside a device) and he could get woken up often. This will fade as he gets used to the device, but if the device is really ill-fitting, it might just get worse and become unbearable. I recommend choosing a device with lots of sizing options, like the CB6000.
Leave a key with him at all times in the beginning (Until he can wear it comfortably for days on end without issue). You can seal it in an envelope and sign the seal. This way, you know if he retreived the key, but it also provides him an option for quick escape in any kind of emergency. It may also ease those fears a little.
Basically, my main advice is this: talk talk talk and take it slow. Do it this way and you can't go wrong.
Chastity is hot! (or it should be) for both of you. For so many reasons. What made me realise how much I loved chastity are the times he cuddles up to me and tells me how much he loves me. What makes me realise he loves chastity? I once threatened to take away his device (I was angry that he had forgot to put it back on after his bath - a few times in a row) and he was pretty upset about that idea! Yeah, we just talk a lot and being honest and forthcoming with worries and concerns helps nip any issues in the bud early. Of course, you also need to know the difference between a problem and a whinge about his situation, because giving in to his every demand puts him in control of the situation and you will begin to wonder why you bothered.
You want to push him, but not break him! hehe
Good luck and if you have any specific questions, just ask!