Actually I am quite agree with Cherry.
There's no rule for you to learn how many certain characters a day.
Even us Chinese natives don't do that when we are studying at school, either.
Try to imagine that if you learnt 20 characters but forgot them all the next day...well it's no use, isn't it?
So I think the most important fact you should know that.
1.When you face a new character, first you need to know how to write it correctly (when it comes to traditional Chinese characters it would be vital because there're more strokes).
2.Then know how to read (usually a character has different pronounciations).
3. The final step and the most difficult step, to know the basic meanings and the most used words via dictionary or other medias.
You should keep following these steps when you learn new characters. It doesn't matter if you just learn 1 character a day, but it does matter if you can't understand every character you learnt well. Good luck!