A start is finding a good therapist and possibly psychiatrist to help you. If you've already done that, then you're on your way.

I'll share what I do about my own suicidal thoughts that have actively been with me since early childhood. I accept that they're there. I accept that my mind seems drawn to the desperate desire to not be in agony. I accept it but I don't do so without letting my thoughts know that I'm the one in charge. They can be present but I hold the power to redirect my mind. How my mind works, I can have roughly anywhere from two to who-knows-how-many thoughts at a time in a twenty second period. My mind isn't quiet and it never truly rests. In a way it's a blessing because I can choose to concentrate more on another thought while still undergoing a suicidal one. Sometimes, the suicidal thought is too loud for my attention to be diverted. When this happens, I redirect my mind externally. I watch something, listen to music, write, draw or do house work. Sometimes I also research random facts and information that I may be interested in.

Hopefully this helps some. Welcome to PC, this is a good place to get things off your chest.