Easy Completion Of Metal City: Mission 1:

Do a back flip off the first ramp. When you have completed the flip, spin until you land to get 10 points. You can perform stunts again on the drop-off just before the two tunnels. Do the same thing to get 8 points. Trick on one of the slopes on the side of the four-lane road. Finally, on the ramp before the end, do a backflip off it. Make sure to release A on the very edge of the ramp. If done correctly, you will bypass the hanging part of the stage and be offered another ramp to trick off from. Use this to get 30 points or more.