I require a larger sized cover (it's a matter of girth) than the standard model the typical provider has on hand. Therefore, I usually bring a couple of my own covers along to the incall.
So what's the best way of alerting the provider to my special need? Should I announce this beforehand or just casually bring it up when the need, eh, arises?

If you need or prefer a specific brand of condom you could bring them in a NEW UNOPENED box.  Many providers have more than one size of condom on hand so let her know and she may be able to accommodate you.  I am not sure how it would be received during a pre-session phone call, text,  or email.

Be prepared for her to veto your choice and elect to use her stash.

I am a fan of a well known name brand and style that works well with my size and I bring a new sealed box with me.  I have yet to be refused as it usually turns out she has the same kind available.  If a lady refuses to open my box, I would defer to her choice and make the best of it. If I planned on seeing her again, I would request she be prepared with my favorites in the future.

Dumbjock

All you have to do is let her try to put one of her condoms on you and when it doesn't fit you can then pull out one of your own condoms. That should do the trick.

I didn't always.  Then, on the way to meet a Fav Lady, I make the call from the highway to let her know I'm past the high traffic area...  and she asks me to pick up covers.  (Offers to reimburse me!)   Now I was in a strange city, did not know the stores, was unable to locate any sort of a premium product & getting off the highway made me very late.  
There are also a number of scams...  involving not having the covers...  so having some on hand offers some protection against that.  

Now I understand a Lady's right to refuse to use covers supplied by others...  but it has never happened.  Once, a lady said "I have them."  I said "I prefer this type".  I know they cost extra & often ladies have different sizes but not necessarily the ultra thin which I prefer.

NO, do not discuss in advance.  After we have a hug & a kiss...  while we are undressing, I just place on the bedside table.  No discussion.   If she cares to inspect them, she can do so while I am in the bathroom.  

I think proper fit is crucial...  must be tight enough to stay put but loose enough to move a bit on the inside...  we are on the inside...  movement creates friction, no movement, no friction, no feeling!

No need to bring it up, but when its about to happen say I brought my own.
Ladies usually only have the standard. and when it comes to safety and you need a larger one please supply it.
You do not want the whole date ruined just because the right equipment isnt provided.



xoxoxo,
Your Rockstar Barbie Doll
Krista Starr

but ONLY in non-latex because of a severe latex allergy (makes me blister and hurt). I never had a client walk away because I didn't use the ones he brought.

I carry a variety of condoms sizes, textures and even flavors (wink).  There is no reason to mention condoms pre-session.  Actually if it's mention before screening is complete I'd never see the gent.  Discussion of condoms have been enough to arrest girls if the discussion was with LE. If you have a preference, bring it with you to the appointment. Chances are that she will already have it in her goody bag.

most ladies prefer using their own