Set the floating point mode on your calculator by pressing the "MODE" button, scrolling down once and pressing "Enter". Return to the home screen by pressing "2nd" then "Mode".
Turn on the calculator diagnostics by pressing "2nd" then "0" then "x^-1." Scroll to find the "DiagnosticOn" option and press enter twice. This information will be saved so do not need to be repeated each time you want to make a scatter plot.
Turn off all other plots, if any, by pressing the "Y=" key and highlighting each active plot then pressing "Enter" to turn it off. You may also delete them if you no longer need them.
Enter the data for each variable into a statistics list. Press "STAT" then "1" to enter the edit screen. If there are already data in the list, place the cursor on "L1" press "CLEAR" then press "Enter". Enter each x-value into column L1. Now, move the cursor once to the right to enter column L2, clearing if necessary. Enter the y-values.
Press "2nd" then "Y=" then "1" then press "Enter" to turn Plot 1 on. Press the down arrow once then press "Enter" to select the scatter plot option. Press the down arrow once more then press "2nd" then "1" to select L1 as the x-axis. Finally, press the down arrow one more time then "2nd" then "2" to select L2 as the y-axis.
Press "Zoom" then "9" to automatically adjust the window to fit the data. Pressing "Trace" will show you each point on the graph individually, as you entered them into the columns. Press the right arrow key to move the cursor over each point.