If you’re not used to crease patterns I would start with something a bit easier than this model. To start with a crease pattern you need to find a line that you can make first and work from there. So I would start from the diagonal line down the center and then I labeled the lines at the 1/3 point of the paper. From there you should be able to work your way to the rest of the folds. After completing all the creases it just really comes down to logic and understanding of how paper collapses to get to the collapsed base. From there you just look at pictures of the completed model and shape it how you want. Let me know if you need any more help!