"如何适度玩电子游戏" 的英文表达可以是：
1. How to Play Video Games Moderately
或者更日常一点的说法：
2. How to Play Video Games in a Balanced Way
3. How to Play Video Games Healthily and Moderately
4. How to Play Video Games Responsibly
5. How to Play Video Games in a Balanced and Moderate Way
一些相关英文表达（根据语境）：
- Moderate gaming – 适度游戏
- Healthy gaming – 健康游戏
- Balanced gaming – 平衡游戏
- Responsible gaming – 负责游戏
- Screen time – 屏幕时间
- Game time – 游戏时间
- Game addiction – 游戏成瘾
一个完整的英文句子示例：
"It's important to play video games moderately, so that you can enjoy them without becoming addicted."
或者：
"To play video games in a healthy way, you should set limits on how much time you spend playing and take breaks regularly."
总结：
如果你想表达“如何适度玩电子游戏”，可以用以下几种方式：
- How to play video games moderately
- How to play video games in a balanced and responsible way
- How to play video games healthily and responsibly
如果你有特定的语境（比如写文章、做演讲、写博客等），我可以帮你润色成更合适的表达。