Sure, I'd be happy to help you with DIY underfloor heating system installation. Here are the basic steps you can follow:

Choose the underfloor heating system: Select the type of underfloor heating system that suits your needs, such as electric or water-based heating. Be sure to consider the size of the area you want to heat and the type of flooring you have.

Prepare the subfloor: Ensure that the subfloor is clean, flat, and dry before beginning installation. If necessary, install insulation to reduce heat loss and improve energy efficiency.

Plan the layout: Plan the layout of the underfloor heating system, taking into consideration any obstacles or furniture that may impact the placement of the heating elements. Use a tape measure to mark out the locations of the heating cables or pipes.

Install the heating system: For an electric system, lay the heating cables in a serpentine pattern across the subfloor, securing them with cable ties. For a water-based system, lay the pipes in a similar pattern, securing them with clips.

Connect the system to power or the boiler: Connect the electric underfloor heating system to a thermostat and power source, following the manufacturer's instructions. For a water-based system, connect the pipes to the boiler or heat pump.

Test the system: Before installing the flooring, test the underfloor heating system to ensure that it is functioning properly. Leave it running for several hours to ensure that it heats the room evenly.

Install the flooring: Once the underfloor heating system is tested and functioning correctly, you can install the flooring of your choice.

It's important to note that underfloor heating system installation can be complex and may require professional help. Be sure to follow safety precautions and manufacturer's instructions carefully to ensure a successful installation.