Here is the material you need to prepare:
1) Dimension for the dog
2) AL tube according to the dimension. x 5
3) Bike flashlight mount.x 6
4) Sponge tube.
7) Wheel x 2
8) AL Tube plastic cap.
And Let's get start.
Step 1: Measure the dimension of the dog
Step 2: Cut and bend Al tube according to the blueprint
Step 3: Drill holes on tube
Step 4: Use screws and bike mount for assembly
Step 5: Adjustable front handle
Step 6: Spong loops to hold the leg
You dog can now go for a ride.