If you're willing to take an active interest in this side of his life, the first step is to meet his female persona. Most TV's who dress fully, with complete female outfits, make-up and wig(s), regard their female self as a distinct personality in 'her' own right - a 'female' individual who is at the same time part of their personality and a distinct departure from their everyday male self, to the extent that you'll probably find that 'she' has a feminine name. This may or may not be a feminised version of their male name - Stephen, for example, may become Stephanie, or may choose a completely unrelated female name such as Mary. (There's also a convention amongst TVs that when 'en femme' they refer to one another as 'girls' - or sometimes 'gurls' - and use the female personal pronoun - so don't be surprised if you hear one TV referring to another as 'she'.....)
Meeting your partner's female self will probably be easier if you first ask him to show you some photographs, if he has any (and he probably will have - most TVs, even those who are total slobs when in male mode, are incredibly vain where their female personas are concerned!)
When you're ready to meet 'her' (and this is another stage you shouldn't try to rush - take your time and wait until you're quite sure you can handle it) try to keep the atmosphere as relaxed as possible - choose a time when you're not likely to be disturbed, and neither of you is rushed or tense. Try to bear in mind that however nervous and apprehensive you are about this, your partner is going to be feeling much worse - he's showing you a side of himself that he may never have shown to anyone before, and making himself extremely vulnerable in the process, so please be aware of and sensitive to the way he'll be feeling.
Once you've got over the first shock of seeing your partner as a 'woman' (and it is a shock, so don't worry if that's all you feel to start with) you may decide you don't want to repeat the experience - as I've said before, you should never feel pressured to do more than you feel you can comfortably cope with, and if you can't handle the sight of the man in your life in such a different guise from the one you're used to, that's entirely understandable.
Do try to remember, however, that underneath the clothes, wig and make-up, this is still the same person that you love and live with. 'He' hasn't suddenly become a different individual - he's just expressing and enjoying the 'she' inside him.
Taking it further
The first time I met 'Trisha' (as opposed to Nick), I was actually fascinated by the way in which he was still the same person, but subtly different - it wasn't (as I'd rather expected it to be) like seeing a 'bloke in a frock', but more like seeing the woman my husband would have been if he hadn't happened to be born male instead of female. The broad shoulders, masculine build and deep voice were jarring notes, of course (as they are for most TVs) and the body language had changed in some fairly subtle ways, but in a strange way it was more like meeting a new female friend that I already knew I was going to like a lot.
If you find yourself reacting in a similar way, great! You and your partner can have a lot of fun together exploring this new side of him, if you're interested. You might be able to offer him advice about clothes, make-up etc. - if so, he'll probably be thrilled, and delighted to have your help in developing his female persona. If he has friends among the TV community (perhaps people he's met online - not all TV websites are primarily contact sites or knocking shops!) you might be interested in meeting them (perhaps in male mode first), of if he's a member of a TV site that welcomes partners you could consider joining too - you'll learn a lot about transvestism that way, and probably get to know some fascinating people into the bargain.
You might also think of going out with him to TV venues, if he's interested in this kind of scene (some TVs are, some aren't). This can be good fun - I started to go out with Trisha about six months after discovering 'she' existed, and I was very warmly welcomed by his TV and TS friends and met some really nice people who have become good friends to both of us.
You may well also find that there are added benefits, as your relationship becomes deeper and stronger - most TVs in my experience like, respect, and understand women, and are absolutely delighted to find that their partners are willing to accept and support this side of them.
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