1. Prepare materials and tools, including angle iron, welding machine, welding electrode, pliers, hammer, wrench, etc., and cut the angle iron into corresponding length according to the size requirements of the bed.

2. Stand up the four angle irons of the bed frame so that they take on the shape of a bed, and use pliers and wrenches to fix the angle irons together.

3. Use a welding machine and welding electrode to weld the angle iron. Contact the welding electrode with the angle iron to trigger the welding machine to start working.

4. After welding is completed, use a hammer and wrench to adjust the bed frame to keep it level and stable.

5. Check the stability and flatness of the bed frame. If necessary, make some adjustments and trimmings, and polish and paint the bed frame to make its surface smooth and beautiful.