Whether it is better to use a mosaic display board by hand or on a hook depends on several factors, including the size and weight of the display board, the display environment, and personal preference. Here are some considerations to help you decide:

1. **Display Environment:** Consider the layout and design of your showroom or retail space. If you have limited floor space or if you want to maximize wall space for other displays or signage, using mosaic display boards on hooks may be a more space-efficient option.

2. **Accessibility:** Think about how easily customers will be able to access and view the mosaic display boards. Displaying boards on hooks at eye level or within easy reach can make it convenient for customers to browse through the samples and compare different options.

3. **Visibility:** Consider the visibility of the mosaic display boards from various vantage points within the space. Depending on the layout and traffic flow, hanging boards on hooks may provide better visibility and allow customers to see the samples from a distance.

4. **Security:** Evaluate the security of the display boards, especially if they contain valuable or fragile mosaic samples. Securing boards on hooks with proper hardware can help prevent theft or damage by ensuring that the boards remain firmly in place.

5. **Aesthetic Considerations:** Think about the overall aesthetic and design style of your showroom or retail space. Depending on the decor theme, hanging mosaic display boards on hooks may complement the design and create a cohesive look.

6. **Flexibility:** Consider how easily you can update or rearrange the display boards as needed. Using hooks allows for flexibility in changing the layout or adding new boards without the need for additional hardware or installation.

7. **Weight and Size:** Take into account the weight and size of the mosaic display boards. Larger or heavier boards may be more challenging to hang on hooks, especially if they require sturdy mounting hardware to support them securely.

Ultimately, the decision to use mosaic display boards by hand or on hooks depends on your specific display needs, the characteristics of your space, and the preferences of your customers. You may choose to use a combination of both methods to create an engaging and versatile display that showcases mosaic samples effectively.