What are some best practices while writing test classes in Salesforce?

When writing test classes in Salesforce, a few best practices can ensure your code is efficient and maintainable. Here are my top five:

1. Aim for 100% Coverage: Salesforce requires a minimum of 75% test coverage, but aiming for 100% means you're thoroughly checking your code. This helps avoid those pesky future bugs!
2. Test Data Independence: Always create your own test data. Use @testSetup annotation to create test records. Remember, Salesforce's 'seeAllData' attribute should ideally be 'false' to prevent access to real org data.
3. Bulkify Your Code: Test for bulk operations to ensure your code can handle multiple records at once. This is a big one - Salesforce is all about managing large amounts of data.
4. Test for Various Scenarios: Consider positive, negative, and edge cases. It's not just about when things go right, but also when they go wrong or barely pass.
5. Avoid Hardcoding IDs: Hardcoded IDs may change between environments which can cause your tests to fail. Better to dynamically identify record types or any other type-based criteria.

I appreciate you for sharing those tips with us.