I made a video about this last week so I figured I should put it here as well, I'll update this guide if I make more videos in the future.

A few other tips I forget to mention in the video are

• Double tapping the acceleration button gives you a small boost
• For WR standards, any split time over 2 minutes is not fast enough
• Use the combo's sparingly, only when you have an excess of ammo or you're sure you will hit. Otherwise you may run out.
• Hot Rod Enemies always spawn with a special weapon and usually always use it as soon as they can
• Keep in mind where the High Value Targets are such as Clyde, Dusty, Sheila, Nina, Boogie, and Chase. All of these characters will either waste time or fuck with your weapons if they have their special weapon.

If you want to learn all of the combos that aren't mentioned in the above video here's a closer look at them and a better look at the base weapons.