just start using them - if you have a blue badge use it you will only realise the impact on your health and anxieties when you start to consistently use them without fear of what others think of you. It will become your routine it is for me. Myself and son both have relatively hidden reasons for needing our blue badges but it has been life changing as we were house bound before we had them. Just don’t worry about other people chances are most people are too busy to even notice who you are and we all are the legitimate users there are plenty of people who park in our spaces even without a badge!