Identify the input values of the function
Determine which input values are allowed
Exclude values that make the function undefined
The set of allowed input values is the domain
Determine the output values produced by the function
Find all possible output values
The set of possible output values is the range
For graphs, read domain from left to right
For graphs, read range from bottom to top
Use algebra to solve for restrictions when needed
Check for square roots, denominators, and logarithms
Use interval notation or set notation to write the domain and range