Cryptographers, teach me how to shuffle cards

Shuffling cards is hard, some methods need skill or are to hard for children to do, others don&#x27;t shuffle the cards well, sometimes the same cards easily stick together.<p>A solution I found is to shuffle cards by distributing them into 4 piles one by one, and then putting the piles on top of each other. It usually does the job of splitting cards that were together previously, and even a child can do the procedure producing a relatively well shuffled deck. But for some card games that doesn&#x27;t work: like Skip-bo where the cards end up in sets of 12 making this method terrible. I tried adding some randomness by randomly picking the piles to place the cards into, but I don&#x27;t feel like it is a good solution.<p>So, Cryptographers, use your hashing and encryption knowledge to come up with an algorithm that could be taught to a child, doesn&#x27;t take more than 2 passes through the deck, but that best eliminates any kind of patterns out of cards.<p>As criteria I will set &quot;being able to shuffle a deck of cards that is sorted or has a repeating pattern&quot; while &quot;requiring the minimal amount of logic and movements from the shuffler.&quot;<p>Maybe, I phrased my entire question badly, but I hope it can be understood.