Help me come up with a strategy for the game Nim? ?

We're playing the game Nim a differen way, we lay out 18 toothpicks vertically in a row. We can pick up 1,2,3 or 4 toothpicks at a time. Whoever picks up the last one wins. Can you help me come up with a solution to win everytime I get to decide to go first or second?? Thanks.
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