At 1.5 not a lot can go wrong. Empty stomach, somewhere comfy - you know the drill. Something that helped me with my first trips was to do breath work and meditation prior. A helpful thing is to be well - rested, because if it's late you may start drifting in and out. Don't go in with any expectations, this will hopefully be the beginning of your psychedelic journey. Remember - don't weigh the marathon on the first 200m.