Do you go out dressed at all? I have taken the walk to the post box and back in stockings and heels. I wear around the house all the time and have had a couple of times when I have thrown a shirt over my bra when an unexpected visitor has come by - postman, etc.
Once was off work sick and went to the doctor. She wanted to listen to my breathing so got the stethoscope and lifted my shirt at the back. I wasn't wearing but had been just before leaving and I felt her trace the line of the bra strap marks. she didn't say anything but when I turned around she noticeably stared at my tits!
Just do it! Maybe not in your own street but you will be amazed at how little attention people pay to what is right in front of them. That is why I like going shopping under-dressed. Short of being hugged and groped to feel my bra - unless I wear a thin shirt that is easy to see through - nobody will see.