To play: from the letters shown on the table, can you make a word? If so, you can discard those letters. Turn over the next card from each pile that you were able to use a letter. You win when all cards from all piles have been used to make words. Making more piles of fewer cards will make it easier to win. Vice versa, do fewer piles if you want more of a challenge. Pro tip: There is only 1 'Q' and 2 'U's in the deck so in this game, you may want to be very careful about when you use your 'U".
Game Play: Deal 7 cards per player. Player with the highest double is first to go and places that card in the center of table to start the game. Play cards if you have an end that matches an open end available. In the picture above, each card matches with the six. The next player to play a card would need to have a 0,5,2,or 1 domino count in order to go next. In classic dominoes, the first card is the only card that can be played off in four directions as shown. If player does not have any playable dominoes, they pull from the ‘boneyard’ of remaining dominoes not yet dealt. Player to discard all their cards first wins the hand and earns points by counting the remaining pips in the other players hand.
Add points throughout: for ‘all-fives’ the goal is play dominoes that add up to increments of the number 5 with the other end of the domino string. For example, in the image above, if the player played a 5-1 domino next to the 1-6 (7 of diamonds), they would score 10 points (5 on the domino they just played + 5 pip end on the card that is also the jack of hearts). If they played a 2-5 domino off next to the 2-6 (ace of hearts), they would score 5 points.
Here's a link to wikipedia with a lot of great info about dominoes to also help you get started!