Method

Place a beaker on balance and zero it
Add oil and record mass of oil
Then place an immersion heater and thermometer in the oil and record the starting temperature
Wrap beaker in insulating foam
Connect a joulemeter and a power pack to the immersion heater
Leave for 30 mins and record temperature and energy transferred
Calculate Specific Heat Capacity This practical could also be done with a 1kg steel block with a hole for the immersion heater - place water in hole with immersion heater to increase conductivity and transfer of energy

Sources of Inaccuracy

Thermal energy passing out of the beaker into the air - Use an insulator with a lower thermal conductivity
Not all thermal energy is transferred to oil - Ensure that it’s fully submerged
Incorrect reading of thermometer - use an electric probe
Thermal energy not being spread through the oil - stir the oil