simplest way is with a motion tween -
make the text into a movieclip(hit F8 - movieclip);
position where you want it,;
right click on the frame that contains the clip in the timeline, choose create motion tween;
click in another frame at the length desired and go insert->keyframe or hit F6;
slect the object on the stage in either frame and ste the color drop downn in the properties panel to alpha, pick a percentage.
if you want it in/out then add another keyframe in the middle of the frames span and set the start end frames alpha value to the same amount - i.e. frame 1 - 0%, frame 2 -100%, frame 3 - 0%;
this can also be done more efiiciently using the _alpha property of the movieclip object.
use a movieclip as before, select it before opening the actions panel and attach this action
PHP Code:
onClipEvent (load) {
alpha_change = -1;// change this value to suit rate and initial direction of fade - negative fades out to start
}
onClipEvent (enterFrame) {
this._alpha += alpha_change;
if (this._alpha<=0 || this._alpha>=100) {//change these values [0,100] to set min and max alpha
alpha_change *= -1;
}
}