Turn off the circuit power before connecting the multimeter
Set the multimeter to current mode, selecting AC or DC as needed
Move the red probe to the current input jack
Keep the black probe in the COM jack
Open the circuit where current will be measured
Connect the multimeter in series with the circuit
Turn the power back on
Read the current value on the display
Start with the highest current range if the value is unknown
Turn off power and move the red probe back to the voltage/resistance jack after measuring
Never connect the multimeter in parallel when measuring current
Never measure current directly across a power source