Avoid losing lives:
To prevent a loss of a loss of a life, press Start
when you have one heart remaining, and select "Retry".
You will go back to the door you went through. This is
good for health.
More lives:
Keep entering the first Hoverboard stage. Get the
first life, then keep going until you get to the hill
with a sign. Jump to get the second life. Then, head
for the finish line, and jump for the last life.