SOURCE: Heidelberg's Lateinische Uebungs und Lesebuecher at GoogleBooks. This is not part of the classical Aesopic corpus, but I like the story!
READ OUT LOUD. Choose which marked text you prefer to practice with - macrons or accent marks - and read the text out loud until you feel comfortable and confident. Then, try reading the unmarked text at the bottom. It should be easy for you after practicing with the marked texts. :-)
MACRONS. Here is the text with macrons:
Stellae certābant dē principātū; suum quaeque splendōrem laudābat. Dum certant, appāret sōl; omnēs ēvānescunt.
ACCENT MARKS. Here is the text with ecclesiastical accents, plus some color-coding for the words of three or more syllables (blue: penultimate stress; red: antepenultimate stress):
Stellae certábant de principátu; suum quaeque splendórem laudábat. Dum certant, appáret sol; omnes evanéscunt.
UNMARKED TEXT. Here is the unmarked text - after practicing with the marked text that you prefer, you should not have any trouble with the unmarked text:
certabant de principatu;
suum quaeque splendorem
IMAGE. Here is an illustration for the story (image source) showing the beautiful bright sun!