Google Page Speed/ PIngdom /Gtmetrix Result Optimization

Hi Guys

I am new to this field of speed optimization according to google page speed results/pingdom/gtmetrix. They ask for various things to be done, such as minifying etc, compression, render block codes etc.
I want to know how to do them all, whether I use plugin or no,
or I just codes, if so how to use them.

Also how to reduce wait time (see image wait)

I currently use hummingbird and autoptimize