How does changing the metal ion in a compound affect the colour of flame it produces when burned?

When metal ions are heated, their electrons gain thermal energy and are able to move to higher energy states as compared to their unexcited state (or ground state). When these excited electrons fall back to their ground states (in one or more clearly defined paths), they release energy in the form of light. The light released has a particular wavelength, depending on the metal ion and the electron jump. In other words, colors are seen corresponding to the wavelength of the light released. And, the colors are characteristic of the metal ions. For example, Copper produces a blue flame, barium produces green flame, and sodium produces a yellow flame.
Thus, if we change the metal ion in a compound, the color of light produced on its burning will be different. And the color observed would be characteristic of the metal ion present in the particular compound. For example, if we replace copper with barium in a compound, the color of flame would change from blue to green.
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