Marketing planning is important but sometimes you will need to go on a project or marketing journey and make the map as you go and that is okay. Not ideal but okay and necessary. If you find you are in this situation, start by thinking of similar projects and what has worked or not worked in the past. Keep your eyes, ears and mind clear and fresh for those decisions that can not be anticipated. And record along the way the journey so you can draw the map and have for future reference.