You could try pureeing some vegetables into a spread to put on toast, I do that with lunch a lot. For example, today she had watermelon, rock melon and some roast pumpkin and lentils spread on toast.

I would just keep offering the water as you are and she will soon get how to do it herself. Have you tried a few different sippy cups? If she is breastfed sometimes the straw like tops can be good (that is what we use) with handles on the side so it is easy to hold. Also don't fill it too much or it can become too heavy for them to maneuver.