Good and Interesting question.
Here are some to make the tester's job easier:
- Developers should perform basic testing before giving the product to the tester.
- Include QA from the beginning of the project, not when the product is ready to test.
- Work as a Team, not as two different departments [Developer & QA]
- As the developer, never ask the QA to ignore bugs. Also, it is not the QA's job to verify that bugs have been fixed.
- Support the QA if they do not have a clear understanding of the product.
- Work toward the common goal of making a solid product. Do not think that you are the developer and they are the tester.