Choosing a mini convection heater can be a simple process if you consider the following factors:

1. Heating Capacity: Determine the size of the room or space that you want to heat. Check the heater's heating capacity or output rating to ensure that it can provide enough heat to warm up the space. The heating capacity is usually measured in watts.

2. Energy Efficiency: Look for heaters that are energy-efficient to help you save on energy bills. Check the heater's energy rating or look for models with features such as adjustable thermostats, timers, and programmable settings.
   

3. Safety Features: Choose a mini convection heater that has safety features such as tip-over protection, overheat protection, and cool-to-the-touch exteriors to prevent accidents and keep your home safe.

4. Size and Portability: Consider the size and portability of the heater. A mini convection heater is typically small and lightweight, making it easy to move from one room to another. Look for a model with a handle or wheels for easy portability.

5. Noise Level: Check the noise level of the heater. Choose a model with a low noise level to avoid disturbances while you work, sleep or watch TV.

6. Price: Finally, consider your budget when choosing a mini convection heater. Look for models that offer good value for money, and check for any special offers or discounts available.

By considering these factors, you can choose a mini convection heater that is efficient, safe, portable, and suits your needs and budget.