Regardless of why your son is having a tantrum, there are some simple guidelines to follow:
First, try to soothe, calm and talk to your child.
If this doesn't work because he is too worked up, let him cry it out in a safe place, stay close by, and leave the talking for later.
Once your child will allow it, gentle holding and reassuring comments can be helpful.
Remember, it's important not to give in to your child during a tantrum. Even if you give in only once or twice, your child learns that tantrums are an effective way to get what he wants.
And above all, try to remain calm amidst the storm. When a child loses control during a tantrum, it can be very frightening for them. They need to know that you are in control, and will keep them safe. Over time, this important learning will help them manage their own strong feelings more effectively.