Gastroparesis is the slowing down of emptying of the contents of your stomach, leading to symptoms of nausea, vomiting, early satiety, and bloating. As others have mentioned, a good thing to start with is diet control. Low fat is a great way to go. However, there are some other things you can try.
I won't assume anything about you, but one of the most common things I see in patients with gastroparesis is Type II Diabetes, so if you have that, the same advice is true. Maintain good glycemic control, weight loss, etc.
Typically, you will need medication at some point. Most people do. Talk to your doctor about metoclopramide.