Describe and label your graph axes purposefully
How many times have you seen presentations where the fonts on the graph axes are too small to read? Perhaps there are 5 or 6 graphs on the page, all with axes that are unreadable.
When you flip on a new slide the listener needs to flip their mental state to start comprehending the new slide. Taking time to explain the axes of your graph is the perfect way to introduce a new slide. Use your pointer and point to the Y axis and tell the audience what it represents. Then do the same for the X axis. Be deliberate!
Axes should be labeled in clear large font (24 bold, Helvetica is great, 18 bold is tolerable, less than that is invisible). Also don't be lazy and reproduce the vertical layout of text that pops out of Excel. Erase it and rewrite the Y axis label in the horizontal mode so the audience doesn't have to bend their necks.