I usually sleeve the cards on card heavy games, so regular shuffling doesn't work for me. Usually, I will give some cards to another player or two and we will all do some shuffling of those cards, then hand some of the cards from our pile to someone else, while taking some of their cards and shuffling them into the group I kept.

Doing this allows for the shuffling to be divided by a few people, making the amount of cards being shuffled by each individual more manageable. It also helps to get the other players involved in set up, which can keep them from being bored.