What i have found the easist way to inject in ventrogluteal, is to stand up and flex your glut which pushes that muscle up and outwards. So now you have this large section of muscle which lys on top and to this side of your glut. Just stick the pin in there and you should be good. Never had any problems that way before, i have once treid injecting there without flexing and i jabbed right into the bone.