First, create a new image, 400x400 pixels and fill the background with the color that you like.
Use Type Tool [T] to type any text that you want.
The color of the text does not matter so fill it with any random color.
Now is the time to add to change the color of your text to make it more 'Christmas-like' Right click on the text layer and select Blending Options...
Layer Style window will open; click on the 'Color Overlay', select the settings that you see on the screenshot or play around with setting to find a better color.
Play around with settings to get the best result.
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