Second most of the advice on here - wear what is comfortable and don't worry about having cycling-specific stuff so long as it is comfy.
My thoughts are:
1) Underwear upper - this is going to be personal choice, but I am uncomfortable in a normal bra and have to wear a sports bra. A good sports shop or department store will be able to find something (for all but seriously extreme sizes) if Mrs Alasdairgf feels similarly.
2) Outwerwear upper - just like in the real world, sizes vary! In
Altura, I can buy anything in a size 14 and it will fit. With dhb I'm a 16, as I am with Foska. With other clothes I might need an 18, if they did but make them
BUT, you don't need to stick to women's clothing. With Foska I am a 16 if I want a women's road jersey. If instead I have a freeride jersey (baggier like a 'normal' t-shirt style), then I'm a medium! The freeride shirts are unisex, but the sizing is more 'men's like', so you can get larger sizes than at the top end of the women's-specific stuff. And it doesn't looke like you are wearing 'mens clothes'
There's also non-cycling gear. You can get wicking t-shirts at outdoor shops, again the sizes vary in that I can be a 14 to 18, medium to extra large, depending on brand and, erm, how big (or not) they expect the bust to be!
If you can go somewhere that stocks a wide range of things to try (e.g. somewhere like Go Outdoors) then there is bound to be something that fits. Plus there will be a good range of mens stuff there which as with the cycling stuff should go up larger if need be. (There is a Go Outdoors near me and they stock cycling gear and walking gear - men's and women's - wide range of sizes. Complete shopping fest!)
3) Lower clothing - I'd agree that here padding is the key thing. There are two ways of doing this - padded shorts, or padded underwear. If you get padded underwear then you get to wear the shorts/trousers of your choice with them - which again don't have to be cycling-specific or outdoor-specific-wicking - they can just be any comfy trews. This may help in that if you can find undershorts that fit, you don't have to worry about where the over-the-top stuff comes from which frees you up from being limited to the size ranges.
I've been fine in this regard with off the shelf sizes - again sizes vary in that with one brand a 14/L is fine and with another brand an L is...well...something I'll be wearing in the future rather than just now (the shorts fit fine at key places like waist, hips, bottom of legs [I don't look like I'm squeezed in to a too small sausage skin at these points], but they come with the expectation of a flat tummy!)
Corrine Dennis, as already mentioned, is the name I've heard most often in relation to good-quality larger-sized women's cylcing gear (I think they go up to a size 20)
Getting out there and trying stuff on, if possible, is a good way forward. I deliberately didn't make my first few orders online because I was unsure of sizing. I would have bought several things in a 16 if I was buying online, but a LBS had a wide range of gear to try on, and I found that would have been the wrong thing to get!
where to get the plus sizes?
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