Also, reduce carb intake. Carbs make you retain more water. Don't cut them out completely, just less than normal.
Some people say to avoid red meat because it digests slower. You don't want anything extra sitting in your intestines if you're trying to make weight.
And make sure you eat some fruits and vegetables to get some fibre, the last thing you want is to get constipated - which is possible is you are dehydrated and eating no carbs and lots of meat.