Yeah DM can be quite tricky but the good thing is that the format of the section is the same every single time. So you'll always be asked syllogyms at the start of the section, venn diagrams in the middle probability questions at the end along with any other sections ive missed. So I wouldn't be able to help a lot without looking at your DM questions and seeing where you struggle specifically but I think the biggest thing that helped me was making using of the whiteboard they give you. Knowing how to use it properly can make some questions super easy.