Take any number in English, count the number of letters in that number's name. This gives you a number to count the number of letters in THAT number's name, and so on and so forth. You will always end with 4. Here are some examples:
8 = EIGHT; 5 = FIVE; 4 = FOUR
17 = SEVENTEEN; 9 = NINE; 4 = FOUR
4743 = FOUR THOUSAND SEVEN HUNDRED FORTY-THREE; 34 = THIRTY-FOUR; 10 = TEN; 3 = THREE; 5 = FIVE; 4 = FOUR
This is also true for vier, if you're doing it in German, and (sometimes) cinco, if you're doing it in Spanish.
TWIN COSMIC NUMBERS
In Spanish, if you encounter 4 (cuatro) or 6 (seis), you will end up alternating between them. Here are some examples:
23 = VEINTITRES; 10 = DIEZ; 4 = CUATRO; 6 = SEIS
100 = CIEN; 4 = CUATRO; 6 = SEIS
57 = CINCUENTA Y SIETE; 15 = QUINCE; 6 = SEIS; 4 = CUATRO
This brings us to...
CYCLICAL COSMIC NUMBERS
These occur if you encounter three or more cosmic numbers and you end up in a cycle. Here is an example in French:
1 = UN; 2 = DEUX, 4 = QUATRE, 6 = SIX; 3 = TROIS; 5 = CINQ; 4 = QUATRE
SYLLABIC COSMIC NUMBERS
This time, count the number of syllables in each number's name. Here are some examples:
53 = FIFTY-THREE; 3 = THREE; 1 = ONE
521 = CINQ CENT VINGT ET UN; 5 = CINQ; 1 = UN
74 = VIERUNDSIEBZIG; 4 = VIER; 1 = EIN