1) First learn the major scales/keys.
You can remeber them as a sentence, if that's easier. The letters are (C)GDAEBF#C#
- and (C)FBbEbAbDbGbCb . I don't know any English tricks for this, but in Dutch you have a perfect sentence made up of these letters. The problem with English is that notes with a sharp or flat aren't just 1 or 2 letters, so if you want to write Ab you have to write "A flat". In Dutch it's just called "As" (same in German). So you can start each word with these letters.
2) Remember that major keys have a rule: Starting from the C, each following key with one flat more or one sharp more goes either a 5th up (with sharps) or a 5th down (with flats).
3) When learning minor keys, remember the following rules:
-Each minor key begins on the 6th of its major key
-Each minor key has 3 sharps less than it's major key with the same name. For example, A minor has no sharps, while A major has 3 sharps. But: D major has 2 sharps, so you can't remove 3 sharps. In that case d minor has 1 flat, etc.
4) Each note that's chromatically 1 key above the other, has 7 more sharps. For example, C major has no sharps and C# major has 7. Cb major has 7 flats, C major has no flats.
Hope this helps!