[makdaddy]

usually you want to start by picking a typeface that 1) is not comic sans and 2) fits the look and purpose of what you're making.

then you'll pick the size and color, use nice round colors, not just random colors that you mouse over and click.

after that, type out what you wanna say, and kern the letters/words accordingly, so that it looks real nice

and lastly, just mess around with text effects. i'm not familiar with GIMP but it must have some "outer glow", "drop shadow", and "gradient overlay" settings or something.

just mess around, see at what works and what doesn't, look at examples, and practice