The Chromatic Scale consists of twelve notes that each are one semi-step apart (it can be compared with the contrary diatonic scale), and is also called the Half-tone Scale. As you can see on the picture below, all notes in the octave are included. Chromatic scales are not very useful as groundworks for a composition, instead they can be integrated as parts of songs. For example, in a sequence of notes such as G - F# - F as a bass walk from the G to the Em chord. This can be referred to as a chromatic movement.
If we take the Chromatic Scale in C as an example, you would play it like this:
Ascending: C, C#, D, D#, E, F, F#, G, G#, A, A#, B, C
Descending: C, B, Bb, A, Ab, G, Gb, F, E, Eb, D, Db, C
You will not find pictures of chromatic scales in all keys, it would be somewhat unnecessary due to the similarities. The formula is uncomplicated: all notes are included. Therefore, the G Chromatic Scale would begin at G and consist of all notes to the next G including one octave.
Use the Chromatic Scale for exercise
This scale can be used for an exercise of the control over your fingers:
Notice the instructions for fingerings: you should mainly alternate the thumb and the middle finger. Begin slowly and play strictly according to the advised fingerings. The exercise can be mirrored for the left hand. As you get more secure, you can gradually increase the tempo. You can also bring in more octaves in the exercise.
Use the Chromatic Scale for a melody
Here is another, more melodic, example:
This short melody line shows how a bass walk made by adding chromatic notes (F# in the second bar and D in the third bar) can be constructed.
Use the Chromatic Scale between chords
Using chromatic notes between chords are a common approach, not at least in jazz. This can be done with single chromatic notes (e.g. a D# note between chords such as Cmaj7 and Dm7) or part of longer sequences of notes.