How to compare string differences between 2 separate column of sheets in Excel-VBA?

Below i have uploaded two images that i have captured from my excel document (Sheet1, Sheet 2) so as to better illustrate what i mean.

Here's a brief description basically, I just want my macros to compare Part Number (column C) from both sheets and find out the differences. And when a string differences is detected between both sheets it will highlight the row on both sheet of BOM-list to indicate to the user the differences in the Part-number(column C). But that is a problem too as seen in the images there is some rows with "space" which the loop have to take care of to prevent comparing an empty string thus giving wrong result.

Sorry for my poor command of English and explanation if its not clear to you. Can someone guide me on this i'm rather aimless on where or how to start and i have to complete this within a week without prior knowledge on excel-VBA programming understanding.