Heat capacity of solid body could be determined by below experiment.
1. Fill in some amount of cold water into the calorimeter. A calorimeter is an aluminum cup and it's thermal capacity is known.
2. Record the temperature $t_w$ of cold water in the calorimeter.
3. Insert a preheated solid body in calorimeter.
4. Record the temperature of mixture.
5. Repeat the experiment up to 4-5 times for good results.