Probably not the answer your looking for, but the first step is to stop giving a f\*ck. My experience is that 99% of people either don´t care at all that you stutter or will be understanding and supportive towards you. Once I internalized that fact, I realized that I am the only one in the room who thinks stuttering is embarrasing or something that should be linked to feeling some kind of shame. Now it´s a lot easier for me to master situations like meeting new people, making a phone call or even giving a speeck or having a job interview. Another tip I have if you are scared of ruining your speech or job interview: Bevore you start, simply tell your audience what´s going on. Tell them that you stutter. That way you adress the elephant in the room and everyone is on the same page. That helps me a lot to relax in situations like that.