Stacks is actually a very simple game. All you need is 14 dice for each player. Each set of 14 dice should be distinct enough that you will have no problem telling whose dice is whose.
Everyone should gather their dice together and roll them into one big pile. Don't make the pile too compact, or you'll have trouble playing.
Turns are very simple.
The current player chooses a die of his color and picks it up.
A. That dice must not be in a stack with another die, only solo dice can be picked up.
The player then has two options
1. Place the dice on a dice of another of the same number.
A. You may not put a die on-top of another of your color dice.
B. You may not place a die on a stack that contains 4 or more dice.
2. Roll the dice. You then MUST place the number you have rolled.
C. If you accidentally knock over a stack of dice, you must return that stack to the way it was.
D. If you cannot place the die in accordance with rule 1, your turn is over.
When a player runs out of playable (unstacked) dice, every other player gets one more turn, then scoring begins.
First put the single dice aside, they do not count. Now examine each remaining stack. The player whose dice is on top gains the value on the dice. Player with the most points wins!
1. Keep track of the other player's score. If someone starts pulling away place your dice on their's whenever possible. Especially on high-scoring stacks.
2. Consider NOT stacking a third dice on a pre-existing, high-value stack. If you are playing with thinking players they will hurriedly close the stack and you won't score anything.
3. Always roll ones. There is only a 1/6 chance your score won't improve. Think about rolling twos as well, since there is a 1/3 chance for improvement and only a 1/6 chance for a lower point value.
You failed to mention that ones are actually worth 10.