I do most of my painting digitally, using textured brushes in Adobe Photoshop on a Surface Pro computer. But I also love painting in gouache, and have recently started practising with oils. You can find some photos and videos of how I go about my paintings here.
Time-lapse of a landscape speed painting
15 minute sketch from photo reference
Time-lapse of scientific illustration of a burrowing crayfish (Engaeus spp.)
<1 hour sketch from several photo references