Getting started with responsive website design

I need to create a responsive layout, but I'm confused on how to start. I've looked up and found many resources, but it's all very overwhelming. Can someone point me in the right direction on how to get started? I can build a html/css website, but have never done anything in regards to mobile.
A few questions:
1) I've read you should build for mobile then move up, is this correct?
2) Should I start off with a template (or a grid, is that the correct term?) If so, any recommendations? This is…
Getting started with responsive website design

See original post by ThroughTheWire