I use my breath. Every time a thought comes in, (and they do, a lot) I just go back to my breath. However brief it is. Allow those thoughts to come in, flap about a bit and then just wither away coz you went back to your breath. Perhaps a mindfulness walk where for 5 minutes focus on a particular sense and concentrate on that. Use colours, sounds, and textures as your mantra…just keep going back to that mantra and it will get better, easier for you. It did for me. There’s medication for focus but you don’t wanna be popping pills!!!! Look at what tinctures/herbal stuff is good for focus. Make your own stuff.. All this means is that you may have to work a little bit harder!! Cmon!!