2. Run-on is two simple sentences incorrectly joined
with no coordinating conjunction and no comma.
Examples:
Wrong 
My roommate wants to win the tour de France someday he
spends hours riding his bicycle.
Write your signature on the line print your name below it.

3. A comma splice is two simple sentences incorrectly
joined with a comma alone.
Examples:
Wrong 
My roommate wants to win the tour de France someday, he
spends hours riding his bicycle.
Write your signature on the line, print your name below it.

4. 1. Reread your sentences.
2. Identify the simple sentences.
3. Separate the sentences with a period.
Examples:
Wrong:
My roommate wants to win the tour de France someday
he spends hours riding his bicycle.
My roommate wants to win the tour de France someday,
he spends hours riding his bicycle.
Correct:
My roommate wants to win the tour de France someday. He
spends hours riding his bicycle.

5. 4. Add (or keep the comma) and add a coordinating
conjunction.
Examples:
Wrong:
My roommate wants to win the tour de France someday
he spends hours riding his bicycle.
My roommate wants to win the tour de France someday,
he spends hours riding his bicycle.
Correct:
 My roommate wants to win the tour de France someday,
so he spends hours riding his bicycle.
IMPORTANT: When you use a coordinating conjunction to correct a
run-on or a comma splice, you must consider how the conjunction will
affect the meaning of the sentence.

6. Example:
Wrong:
Write your signature on the line print your name below it.
Write your signature on the line, print your name below it.
Correct:
Write your signature on the line. Print your name below it.
(Separate the sentences with a period)
Write your signature on the line, and print your name below it.
(Add or keep the comma and add a coordinating conjunction.)
Information taken from: Hogue, A. (1996).
First steps in academic writing. Longman: N.Y.