Decrease Page Load Time on Website

I am running reports from speed test websites and it is saying that my page is loading too slowly and giving lots of suggestions on how to improve the load time, however I am unsure how to implement most of these changes. I need someone to review the critical items and make adjustments to make my home page load faster. This project is urgent as we are trying to get our new site online as quickly as possible and we don't want to put it online if google views it as a slow website and possible ranks us lower.