It is very important to have a speedy website for getting your keyword in the top rank. Google usually picks up the speedy site when visitor search anything on Google. So if your site is not speedy enough and you want to get the top position, then unfortunately it is almost impossible. Google wants to help its visitors by providing quality site. A site with good user experience and high page speed get more priority from Google.
Do it one after another. When all done, then check your speed test once again and you will see some positive impact on your speed test score.
You have to follow the same things for minifying CSS too. To minify CSS you can go to this site http://cssminifier.com/
If you see that your page speed score is above 85 then its OK. But the more score you have the more benefit your site will get. So try to speed up site at anyhow.
If you have any other question on how to speed up a site, then feel free to leave your question in the comments section.
Now check your website’s speed