Tap on the icon displayed in the top right corner of the screen to open up the game menu. Tap on Gifts to open up the Gift Menu where you will be able to send and collect gifts of Coins, Spins, and Cards. As noted at the bottom of the Gifts menu, Spins and Coins which are sent to friends are not taken from your balance.
When it comes to Spins, you can send and receive up to 50 each time! With Coins, the range that can be sent and received differs depending on the Village level.