Do not use "will" to talk about what you have already decided or arranged to do -I'm going on holiday next Saturday "I'll call you when I get home from work" is a sentence with two parts: "I'll call you" (the main part) and "when I get home from work" (the when part). The sentence is future (tonight), but you cannot use will or going to in the when part of the sentence. Instead we use a present tense, usually simple present (I do).

You don't use "will" if the clause indicates the time of the main action (ie. if the clause begins with until, when, after, before, as soon as, etc), or if the clause is the "if-clause" of a first conditional sentence. These clauses are kept in simple tense, so the reader's focus is directed towards the main clause.

After any subjects like I, you, he, she, we, they, personal names (Charles, George, Sabrina, Adelya...)

it can use to any subjects like "I will, we will, they will and any more..