Make sure you have all the necessary tools and parts on hand: Allen wrenches (sizes 3, 4, 5, and 6), spanners, bike grease, and possibly a torque wrench. Mounting on a work stand is easier and more precise.

Insert the handlebars into the stem and tighten the screws. Make sure the handlebars are correctly aligned.

Insert the front wheel into the fork and tighten the axle. Observe the manufacturer's torque specifications. Grease the axle thoroughly with bicycle grease beforehand.

Make sure the brake calipers and lines are installed correctly.

If the brake caliper is not yet mounted on the fork, attach it loosely for now. Remove the brake pad and carefully insert the front wheel with the brake disc into the brake caliper.

Caution: Never press the brake lever while the brake blocker is removed.

Align the brake caliper so that the disc does not rub when the wheel is turned, and then tighten the screws completely.

Check the brakes are working.

Screw the pedals into the cranks (right = right-hand thread, left = left-hand thread). Be sure to use bike grease on the threads.

Mount the saddle, adjust it to the desired height, and tighten the screw. Observe the torque specifications.

Check the tire pressure and inflate the tires to the recommended pressure.

Check the gearshift to ensure it is functioning correctly and that the gears change smoothly and cleanly.

Go through all the screws and connections and make sure everything is tight.

Take a short test ride to make sure the bike is working perfectly.