Learn French: Comment se fait ce vieux rituel ?

This is the pronominal passive. In French, when an inanimate thing (like ce vieux rituel) undergoes an action, it is very natural to use a reflexive pronoun (se) with the active verb rather than the literal passive voice (est fait). It translates smoothly to "is done" in English.

Why is the subject ce vieux rituel at the very end of the sentence?

This is a question structure called stylistic inversion. After an interrogative word like Comment, it is common and elegant to put the noun subject right after the verb instead of before it. In everyday spoken French, you might also hear Comment est-ce que ce vieux rituel se fait ?

Why does the adjective vieux come before the noun?

Most French adjectives go after the noun, but vieux belongs to a small group of common adjectives that come before it. A helpful memory trick is the acronym BANGS: adjectives describing Beauty, Age, Number, Goodness, and Size almost always go before the noun.

Why is the adjective vieux used here instead of vieil?

Both mean "old" for masculine singular nouns. However, the special form vieil is only used when the word immediately following it starts with a vowel or mute h (like in un vieil ami). Since rituel starts with a consonant, we use the standard form vieux.