Using BurpSuite Intruder for fuzzing:
The payload sets determine which list will be used to a determined parameter. Choose simple list. For payload Options for example, select the lists Fuzzing — Full and Fuzzing — SQL Injection.
Additional options are selecting Grep to match with info in response, for example
SQL. And the timeout option can be useful to bypass rate limit or some WAF’s. If there is a redirect parameter in the request, activate the option Follow redirections. Note that sometimes an error can trigger before the redirect, so test both.
Analyse the response code of any anomalies, status code is important and look at the Length column: A bigger length could be an error in the response page.