This is as much help as I would give to my students...

Use two numbers for hours, one less than 40 and one more than 40.
Write the calculations that you would perform to compute the payment in
each case.
Now think variables/cells. Realize that the two different hrs amts
would be placed in the same cell for two different calculations.
Replace numbers with cell references.

Then write your IF. It can accommodate two different calculations based
on the condition, which has to do with the hours.

And stop thinking that you cannot do it. Once you first do it you will
realize your potential. You might not get the Nobel Prize of computing
but you can certainly learn to think as the tool requires.

HTH
Kostis Vezerides