Common knowledge: What does that mean? Common knowledge refers to facts that most people are aware of, for example:
The sun rises in the east and sets in the West
Thirteen colonies formed the United States
John Lennon was assassinated.
Your own opinions/ideas: "It is a mistake to overlook smaller, lower profile markets because..."
Keep track of your sources: Start saving sources as you find them in order to stay organized. Save them to a citation management tool (like Zotero, see Citation Tools tab), email them to yourself, or print them out.
Take good notes: Keep track of page numbers and mark sections of text that you use. Keep a research log; copy the wording, punctuation, and spelling exactly as it appears in the original text. This will save you lots of stress later.
Ask your professor: Always verify with your prof if unsure of whether a citation is required.
Don't procrastinate: Unintentional plagiarism is usually the result of disorganization. Follow these tips and don't wait until the last minute.