Depending on the style of bra and the top, I have found that I can control the look of my breasts, a tactic women use all the time. As most men, I had (incorrectly) assumed that women's breasts were always on display, because that is what breasts do, right? No so. If you pay attention, most women, in non formal or semi formal situations or casual or relaxed situations, wear tops that do not show off the contours of the breast. There may be two bumps that are visible, but you don't see the contour of the breasts as you would in a dress or form fitting top that a woman would wear in a work environment or in a more formal situation that is meant to draw attention to the chest. Once I realized that and saw what they were wearing for the look, I started to convert that look into what will work for a man and I was amazed at the results.
What exactly do you mean by this? I would love to have the support of an underwire without having a big obvious feminine-looking bust, but I can't seem to pull it off.
You have all styles of bras like underwire, soft cup, minimizers, bralettes, unlined, molded cup, stitched (also known as cut and sew), tee shirt, plunge, full coverage, demi, side support, bottom support, wide gore, narrow gore, push up, tall wires, short wires, sports bras and their variants. All can shape/project the breasts in certain ways. Women's clothes demand all different styles of bras to shape the breast to a specific look depending on the top/dress that the woman wants to wear. We can use this to our advantage as well. One would think that if you wear an oversized shirt, problem solved. But actually, you are drawing attention to yourself because now your top is too large and it looks out of proportion to the rest of your body.
If you have breasts that that look more than pecs, you can't totally hide them. You have to find a way to disguise/camouflage them. Women do this all the time. How many times do you see a woman and you can't remember anything about her breasts? She has breasts, right? You didn't notice them. Your eye was never drawn to her chest due to the way she was wearing her clothes. This works the same way for us. Just this morning, I had to go to the doctor. She knows about my gynecomastia. We discussed it, as usual. She asked me if I was wearing a bra. I said I was, and she said that she hadn't noticed before I set down and couldn't really tell without looking closely and even then she wasn't sure. She asked me had increased in size because the way I was dressed, she couldn't tell. She congratulated me on getting the support I needed without looking like a guy in drag. I think she was impressed! So, yes, it possible to tone things down.
Myself, I will wear non-fitted tops, button downs and polos. The polos are usually one size larger than I wear, but you have to be careful not to get the too big look. I will get tops in dark solid colors (NOT WHITE! or white variants, it's like wearing a neon sign advertising your bra/breasts!) and muted patterns to confuse the eyes, BUT NOT STRIPES! Stripes will outline your curves. That is why women don't wear stripes because it adds the illusion of weight to their bodies. I usually wear a form fitting woman's layering tank underneath because a man's undershirt is too warm when wearing a bra and is too bulky under a polo, where the woman's layering tank is made to smooth out the look without being bulky or warm. When it comes to tee shirts, I will wear either one or two sizes larger, depending on the cut, but around the house, I will wear my regular size and let the girls "come out to play" but if I leave the house, I will either add a layer on top or will put on a different top depending the situation and weather.
Something that bothers me is since men's shirts do not have any room in the chest for breasts, the cloth will pull down on the breasts and be uncomfortable. This will cause me to slump to compensate for the discomfort and not only messes up my posture, which can screw up my back, but will also draw attention to me since slumping or slouching is not a normal posture so I have to be careful how I gather the front of the shirt to give enough room for the girls, but not to show them off. It's a fine line.
These are all things I learned from female friends or from observing women in the wild.