Another tip - once you're happy with your text (but before you Merge All Layers), try selecting the "Multiply", "Screen" etc tabs in the Layer Manager section. This will alter the look of your text just as it does with top layer images - it can make it look transparent or give it different effects so that it will show up better against your picture.
Also, try the Effects tab also in Layer Manager. If you scroll down, there is an effect called Plastic Text, which I like using. It kind of makes the text pop. Again, it's trial and error - try sliding the little triangle up and down the scale once you have selected Plastic Text and watch how it changes the appearance of your text! I hope this helps.