Dear contest holder,
while zvercat27 has already presented a step-by-step brief version, there's no point in me presenting you the same. I can however, offer you an alternative in the same aimed retro style of way which I'm hoping you'll give a chance. Kindly read the description along with the comments in entry #70 , whereas I've broken the idea down for you and pointed out to few things.
Thank you in advance for consideration!