Welcome at AT liveinpeace.
There are lots of existing threads on the topic of shuffling. Instead of holding the cards at the top and bottom to shuffle, you can try holding them by their sides. Or you can do the mix them up on the table thing. You can randomly deal the cards into X number of piles and then rejoin the piles. You can also hold the deck in one hand and with the thumb of your other hand you can pull a couple of cards off the top of the deck, then grab a couple off the bottom of the deck (placing those on top of what's already in that hand) and continue until all the cards end up in your other hand.
There are almost as many ways to shuffle as there are people on this forum....
HTH,
Rodney