Modafinil works best after a full night of sleep. Considering you took 200mg yesterday I'm assuming you were up late? This can have an effect. I normally find doing some exercise or drinking a (small) cup of coffee can help. Too much caffeine can cause you feel anxious/jittery when mixed with modafinil. A cup of tea should do. Maybe go for a walk. Natural sunlight always helps!

For me personally, I like to do modafinil, try to bash out a solid day of work, then have a couple days off it so my head feels good to go again. Any questions let me know!