Once again, a silly, simple question

How do you put color in a post? i mean, like make one word blue, another purple, etc.

Courage,my soul, now learn to wield
The weight of thine immortal Shield.
Close on thy Head thy Helmet bright.
Balance thy Sword against the Fight.
See where an Army, strong as fair,
With silken Banners spreads the air.
Now, if thou bee'st that thing Divine,
In this day's Combat let it shine:
And shew that Nature wants anArt
To conquer one resolved Heart.