Learn Hardcore Polish: On zawsze ustawia budzik wieczorem. - He always sets the alarm in the evening.

Zawsze ustawia budzik wieczorem. is perfectly natural. Keeping On adds clarity or contrast (emphasis on “he” rather than someone else):
On zawsze ustawia budzik wieczorem. = He, in particular, always does this.

Can I move zawsze and wieczorem around? What changes?

Yes—word order is flexible, and changes mostly affect emphasis:

Neutral: On zawsze ustawia budzik wieczorem.
Also neutral without pronoun: Zawsze ustawia budzik wieczorem.
Time in front (slight emphasis on when): Wieczorem zawsze ustawia budzik.
Emphasizing the person (can sound contrastive/complaining): Zawsze on ustawia budzik (wieczorem). Avoid overly scrambled orders unless you want strong emphasis.

Is ustawia the most idiomatic verb with budzik, or should I use nastawia?

For alarms, nastawiać/nastawić is the most idiomatic:

On zawsze nastawia budzik wieczorem. Ustawiać/ustawić is understandable and not wrong, but nastawiać is what people typically say for setting an alarm. Use ustawiać more for arranging/positioning or setting parameters in general. Both can appear with a time: nastawić/ustawić budzik na siódmą.

What aspect/tense nuance does ustawia have here?

Ustawia is imperfective present and expresses a habitual action (like English “He always sets…”).

One‑time future: Ustawi budzik wieczorem. (He will set it this evening—once.)
One‑time past (completed): Ustawił budzik wieczorem.
Past habitual: Ustawiał budzik wieczorami.

Is there a separate present continuous in Polish?

No. Polish present covers both simple and continuous. Context words show continuity:

What case is budzik in, and why doesn’t it change form?

Budzik is masculine inanimate, accusative singular. For masculine inanimate nouns, the accusative equals the nominative, so it stays budzik.

Nominative: budzik
Accusative: budzik Contrast: masculine animate changes (e.g., pies → widzę psa).

What is wieczorem exactly, and what’s with the -em ending?

Wieczorem is the instrumental singular of wieczór used adverbially to mean “in the evening.” It’s a common adverbial time pattern:

rano (in the morning), wieczorem (in the evening), nocą / w nocy (at night), po południu (in the afternoon). For repeated evenings, you can say wieczorami (“in the evenings”).

Should I say w wieczorem for “in the evening”?

No. Say simply wieczorem. Use a preposition only when combining with another time word:

How do I pronounce the tricky parts?

On: like English “on.”
zawsze: roughly “ZAHF-sheh” (the w devoices to an F sound before sz; stress on the first syllable).
ustawia: “oo-STAH-vya” (stress on STAH).
budzik: “BOO-jeek” (the dzi is a soft “dj” sound; stress on BOO).
wieczorem: “vye-CHOH-rem” (the cz is like “ch” in “church”; stress on CHOH). General rule: Polish stress is almost always on the second-to-last syllable.

If the subject is female, does anything change?

In the present, no:

How do I say “the alarm” if Polish has no articles?

Use a demonstrative if you need to specify:

ten budzik (this/the alarm clock)
Or possessives: jego budzik (his alarm), swój budzik (his/her own alarm).

I often hear sobie with this verb. Why?

Adding sobie means “for oneself,” which is natural with alarms:

On zawsze wieczorem nastawia sobie budzik. (He always sets himself an alarm in the evening.) It’s optional but very idiomatic.

How do I say “not always” correctly?

Use nie zawsze before the verb:

On nie zawsze ustawia budzik wieczorem. Avoid zawsze nie, which is ungrammatical in this meaning.

Does budzik mean only a physical clock, or also a phone alarm?

It refers to both. You can clarify if you want: