Write the word out on paper in loosely spaced letters, about a quarter inch in between each letter. For example, write the word "h a p p e n" or "a p a r t m e n t." Speak the word aloud and pay attention to the number of vowel sounds in it. For example if the word is "happen" say the word slowly as "hap - pen." Say the three-syllable word "apartment" slowly as "a - part - ment."
Make a slash mark in between the main sounds of the word, the syllables. Count the letter clusters separated by the slashes to calculate the number of syllables in the word. In the example of "hap/pen" the slash will fall between the two p's, showing two syllables. Separate the word "basket" between the s and the k as "bas/ket". Notice words in which the letter y makes a syllable, as in the word "energy" and place slashes according to the syllabic sounds, like this: "en/er/gy." Find words in which two vowels fall next to each other but make separate sounds, like the word "diet." Place the slash between the i and e as "di/et". Look for rare consonants that make a syllable. For example, in the word "mumble," b, l and silent e make syllable.
Count the number of vowels in the word, if simply speaking the word did not clearly tell you where to put the slashes. Draw a line through all silent vowels, such as e at the end of "have." Draw a line through a letter from any diphthongs in the word, like in the word "cheat" which uses two vowels to make one sound; the number of vowels you are left with will reflect how many syllables are in the word. For example, in the word "teacher," there are three vowels; subtract one vowel for the diphthong of ea, so that the final number of vowels is two for two syllables in "teach/er."