I often start with something that inspires me from another song, I might hear a moment that doesn't develop in the way I expect, so I basically take those few seconds or part of a riff and develop it into the way I imagined. Then it's an issue of time, like combining these moments and letting them gestate until they feel like they're a complete song. It usually takes a long time, I try not to force out a song, because ideas are always bubbling in my mind and I feel like they come out when they're ready.