An Infinite Water Source is a little pool that has infinite water. The easiest infinite water sources are 2x2 squares or 3x1 rectangles. Both only require 2 water buckets.
2x2 squares[]
The simplest Water Source:
Step 1: Dig a hole 1 block down, 2 blocks wide and 2 blocks long.
Step 2: Fill in 2 opposite corners with water.
Step 3: Get a bucket and take all the water you want!
3x1 rectangles[]
The 2nd simplest Water Source:
Step 1: Dig a hole 1 block down and 3 blocks wide.
Step 2: Fill in the 2 ends will water.
Step 3: Get a bucket and only take water from the middle.