In the beginning, I just kind of decided what I wanted and then counted up the points... (I had 40 points, so it wasn't an issue)
Now, I usually plan to have about 6-7 pts for breakfast. 8-10 pts for lunch, and then leave the rest for dinner & a snack. Whatever happens to be leftover that's how it works.
As I plan more meals, then it's not just the dinner that I work out ahead of time, but my whole day. Certainly, though, I may think "Hey I want BBQ chicken for dinner tomorrow... I'll have x for lunch so that I can do that." All workable. All normal.
I hope that helps a little.
Any other questions, ask away!!!