Here are a few options for a WordPress post tag description with the title “使用指南” (Usage Guide) in Traditional Chinese, depending on the intended audience and context:

**Option 1 (General and concise):**

> 如何使用本站資源和功能。 (How to use the resources and features of this site.)

* **Why it works:** Clear, direct, and suitable for a broad audience. Uses common verbs.

**Option 2 (More specific about the content focus):**

> 網站、軟件或產品的使用說明和操作教程。 (Instructions and tutorials for using websites, software, or products.)

* **Why it works:** This description hints that the tag relates to how to use websites, software, and other technologies.

**Option 3 (Focusing on learning):**

> 學習如何操作和掌握本站提供的各種功能。 (Learn how to operate and master the various features provided on this site.)

* **Why it works:** Emphasizes the learning aspect of the guides, appealing to users who might be looking to become proficient.

**Option 4 (More detailed and welcoming):**

> 這裡提供詳細的使用說明，協助您輕鬆上手，充分利用本站的各項功能。 (Here are detailed usage instructions to help you get started easily and make full use of all the features of this site.)

* **Why it works:** Aims to be more welcoming and assuring, making users feel guided.

**Option 5 (If the guide relates to a specific section/topic):**

> [添加特定主题的名称，例如: 購物流程/訂閱服務] 的使用方法，教你輕鬆上手。 ([Add the name of the specific topic, e.g., shopping process/subscription service] How to use them, teaching you to get started easily.)

* **Why it works:** Adjust this version to include what is being taught. This is very informative and targeted.

**Choosing the best option:**

Consider the following when selecting:

* **Target Audience:** Who are you writing for? Technical experts? General users?
* **Content Type within the Tag:** Is it focused on one particular thing, or does it cover a variety of topics?
* **Tone:** Do you want to be formal, friendly, or technical?

I recommend **Option 1** as a good starting point for its simplicity. You can then adjust it to become more specific. Remember to choose the option that best reflects the type of information within the posts tagged with “使用指南.”