You need to give credit to sources for several reasons:
To let your readers know how your views, "agree with, disagree with, or modify the views of published experts in the field."
Source: Plagiarism (PDF) - UWGB Writing Center handout
Keep Track of Your Sources
As you search across Google, the library website, and other resources, save materials you plan to use. Either print them out or save them electronically.
Take Good Notes
Keep a list of all the sources (incl. page numbers or URLs) you gathered. Mark the section(s) of sources your will using.
Ask Your Professor
If you have a question about integrating sources into your paper, ask your professor.
Plan ahead! Do not wait until the last minute, as this will lead to sloppy work. Stay organized.
e.g., the sun rises in the east and sets in the west.
The thirteen colonies formed the United States of America.
The capital of Wisconsin is Madison.
Your own opinions and ideas
Consult these resources for more info: