Use paper plates and put one food item per plate. Some patients won't drink liquid if it has already been poured into a glass. However, if you let the patient see you pour the liquid into the glass, they may remember to drink it. Provide contrast between the food and the plate. If the food is green, a white plate makes for good contrast.
Many patients have problems with color discrimination.
If you put all the food on one single plate, rotate the plate often so the patient gets to see all the food on the plate. Try to serve five or six small meals during the day, instead of three large ones. Patients have short attention spans and cannot deal with long meals. Some patients have trouble swallowing thin liquids. You can use a thickening agent or use things like gelatins, puddings or ice cream.