No offence, but if you have no idea on how to edit the build prop, then you shouldn't edit it at all
That said you should install Build prop editor from play store. It's a free app from JRUMMY.
Sent from my HTC One using XDA Premium HD app
Editing build.prop is very easy. But to understand it better you should google around for a guide that shows what each line means and what lines can be modified for your device. I also suggest that you don't delete any lines depending on your rom and instead add any tweaks you may want.
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