Twilio provides various tools and best practices to help customers combat fraud, including standardizing phone numbers in the E.164 format, using Line Type Intelligence Lookup API to detect VOIP numbers, and verifying ownership of phone numbers through Twilio Verify. Implementing these measures can reduce the risk of fraud and improve account security for users. Additionally, limiting the number of accounts associated with a single phone number, detecting excessive sign-ups from suspicious line types, and utilizing carrier MCC/MNC information can also aid in preventing fraudulent activities. By following these guidelines, companies can enhance their account security and protect their users' accounts from scammers and spammers.