What must you be careful about, when putting on a wheel?

You answered correctly. When putting on a wheel, it is important to tighten the wheel nuts with the prescribed torque to ensure they are neither too loose nor too tight. You should also tighten the nuts alternately in a cross pattern, which helps distribute pressure evenly on the wheel and prevents warping. Checking the wheel nuts only after 500 km is not sufficient and is not a required immediate step during the installation process. Remember these steps whenever you mount a wheel to ensure safety and proper function.