Design and implementation of causal band-pass filter for biosignals - what to consider?
Your bullet list makes sense and you seem to have the right idea. I think you mostly want a link that will show you how to get started, so let me suggest this.

First, start with an FIR filter. A very good FIR filter can be generated with as little as 10 lines of code, and implemented with another 10 lines of code. Basically, with FIR, if it's complicated, you are doing it wrong.

This link has source code for Windowed FIR, Parks McClellan FIR, and IIR filters, as well as code for implementing both FIR and IIR filters. Start with the Windowed FIR. They work great and are the simplest to generate.

http://www.iowahills.com/A7ExampleCodePage.html