You need the exact model of your laptop. Then, go on youtube or use google to find a video/instructions on how to open the lid so you can access the LCD. (Usually, I don't even need a video. It's just a matter of prying the bezel off, or removing half a dozen screws). Ideally, do this before you order a new part. Some laptops can have the same model number (e.g. Inspiron 1545) but use different screens (differing in resolution, or in CCFL backlit vs LED backlit). Once it's open, read off the exact model number of the screen itself. Now, go on ebay and use the combination of computer model and LCD model to find a matching screen. Most cost less than $100. Reverse the disassembly process and you're done.