When it comes to custom period cup packaging, there are several important parts to focus on:
1. Branding & Messaging: Successful menstrual cup packaging needs to effectively reflect your brand identity and communicate your brand image to your target customers.

2. Informative: It’s important to present all comprehensive details clearly about the product, including usage instructions and any relevant information that the consumer needs to know. 

3. Sustainability: Consider eco-friendly, biodegradable, and recyclable packaging materials (paper stock, plant-based printing ink, etc.) to align with the environmentally friendly nature of the product itself. This can enhance the appeal of the product to environmentally conscious clients.

4. Eye-catching: The packaging should be visually appealing enough to capture the attention of potential customers and stand out on shelves. Hiring a professional designer to work out a vibrant and engaging graphic design is a crucial part of successful menstrual cup packaging.

5. Protection: The packaging boxes must be sturdy and durable enough to protect the menstrual cups from damage, ensuring they reach the customer in safe and perfect conditions. Durable packaging also reflects positively on the perceived quality of the product. This adherence assures consumers of the product’s safety and reliability.

6. Regulatory Compliance: Ensure that the packaging complies with your local packaging laws, regulations, and standards for menstrual products in your target marketplaces.

By carefully incorporating these elements into your custom period cup packaging, you can create a compelling representation of your brand that resonates with your target audience and sets your Menstrual cup line apart in the market.