Determining the appropriate source(s) for your speech involves more that just identifying something that is on-topic. It involves a critical analysis encompassing all aspects of the source, its context, and how you plan to use it.

SIFT is a handy acronym to help you sift through all the information may find on your topic. It outlines a four-move strategy for which you would:

1. Stop. Remember your purpose. Ask yourself what you already know about the creator/author or the source.
2. Investigate. Know what you are reading about before you read it.
3. Find. Find coverage or consensus on the primary claim of your source before trusting it.
4. Trace. Trace information back to the original source to re-contextualize it and gain a better understanding.

The concept of SIFT comes from Mike Caulfield. It is reused here under a Creative Commons license.