Question : Problem: How do I properly apply thermal compound to a heat sink?

I recently had to remove a heat sink from a processor to fix an issue with a mounting bracket.  I am now ready to reattach the heat sink over the processor.  Should I reapply thermal compound.  I am using the same heat sink and processor as before, nothing changed.  What are the steps to properly remove the old compound and how to I properly apply the new compound?  This ia Pentium 4 processor 1.8GHz in a Dell Dimension 2300.  

Answer : Problem: How do I properly apply thermal compound to a heat sink?

First very thoroughly clean both the CPU's and the heatsink's surface from any residue of the old thermal transfer paste or thermal pad. Use alcohol to do that. Then, when everything is blank and shiny, apply a very small drop of fresh thermal transfer paste to the CPU's surface, and after that just firmly reattach the heatsink.