OpenZeppelin Learn guides: https://docs.openzeppelin.com/openzeppelin/
Guides and tutorials in the forum: https://forum.openzeppelin.com/c/general/guides-and-tutorials/23
Play Ethernaut smart contract security game:
https://solidity-05.ethernaut.openzeppelin.com/
Follow the community guides if you get stuck: Ethernaut Community Solutions
Read through some past security audits:
https://blog.openzeppelin.com/security-audits/
Share your coding journey:
https://forum.openzeppelin.com/tag/coding-journey
Ask lots of questions in the Community Forum: https://forum.openzeppelin.com/
This is a wiki, feel free to update/edit