Learn Hardcore Swedish: Hon planerar sitt schema precis nu, så stör henne inte. - She is planning her schedule right now, so don’t disturb her.

Swedish uses the reflexive possessive sin/sitt/sina when the possessor is the subject of the clause. Here, the subject is Hon, and she is the one who owns the schedule, so use sitt (neuter) with schema: sitt schema.

Use sin for common-gender singular nouns (en): Hon tvättar sin bil.
Use sitt for neuter singular nouns (ett): Hon planerar sitt schema.
Use sina for plurals: Hon läser sina mejl. If you say hennes schema, it typically implies “someone else’s schedule (belonging to her),” not the subject’s own.

Could I say just nu or just nu instead of precis nu? Any nuance?

Yes:

just nu = “right now” (very common and neutral)
precis nu = “right this moment” (adds a tiny bit of emphasis)
nu = “now” (fine, a bit less emphatic) Don’t confuse precis nu (now) with precis nyss (just a moment ago, i.e., past).

How do Swedes express the English “is planning” (present continuous)?

Swedish often uses the simple present:

Hon planerar sitt schema (just nu). To stress ongoingness, use the progressive construction:
Hon håller på att planera sitt schema.
Colloquial variant: Hon håller på och planerar sitt schema. All are correct; the progressive versions highlight the activity is in progress.

Why is there a comma before så?

When så links two main clauses with a result/“so, therefore” meaning, Swedish typically uses a comma:

Det regnar, så vi stannar inne. In your sentence, … precis nu, så … follows this rule. It’s standard and recommended.

What exactly does så do here? Is it the same as så att?

Here så is a coordinating conjunction meaning “so/therefore,” introducing a consequence: … so don’t disturb her.
It is not så att (“so that”), which introduces a result or purpose clause:

Result: Det var sent, så att vi hann inte.
Purpose: more often för att: Vi viskade för att inte störa henne.

Is så stör henne inte the only correct word order for the negative command? What about så stör inte henne?

Both are grammatical:

Stör henne inte (verb + pronoun object + inte) is very idiomatic.
Stör inte henne (verb + inte + object) is also common, especially in speech or if you want to stress henne. With a full noun, Swedes typically place inte before the object: Stör inte läraren.

Why is it henne and not hon or hennes?

hon = subject form (“she”): Hon planerar …
henne = object form (“her”): … stör henne inte.
hennes = possessive (“her/hers”): hennes bok For gender-neutral language, you can use hen (both subject and object), possessive hens.

Is the imperative form really the same as the present tense here (stör)?

Yes. For the verb störa, both the present tense and the imperative are stör:

Present: Hon stör mig.
Imperative: Stör mig inte!

Could I drop så and just say Stör henne inte?

Yes. Stör henne inte is a perfectly fine stand-alone command. Including så links it explicitly to the previous statement as a consequence (“… so don’t disturb her”).

Can I move the time phrase? For example, Just nu planerar hon sitt schema?

Absolutely. Common options:

Hon planerar sitt schema just/precis nu.
Just/Precis nu planerar hon sitt schema. (Initial adverbial; note verb-second order: verb comes before the subject)
Nu planerar hon sitt schema. All are natural; pick the one that fits your emphasis.

Why is it sitt schema (indefinite) and not sitt schemat (definite)?

After a possessive (min, din, hans, hennes, sin, etc.), Swedish uses the indefinite form of the noun:

min bok (not “min boken”)
sitt schema (not “sitt schemat”) Without a possessive, the definite is fine when context requires it: Hon planerar schemat.

How is schema pronounced and what gender is it?

Gender: neuter (ett-word) — ett schema, schemat (definite), scheman (plural), schemana (definite plural).
Pronunciation: initial sch is the Swedish “sj”-sound. Approximate: “SHEH-ma,” with a long first vowel. In IPA: [ˈɧeːma].

How do you pronounce stör and how is it different from stor (“big”)?

stör has ö (like French “eu” in “peur”), IPA [støːr].
stor has o (like English “oo” in “door” but more closed/long), IPA [stuːr]. They’re minimal pairs; vowel quality matters.

Are there alternative, natural ways to say “plan her schedule” in Swedish?

Yes, depending on context:

planera sitt schema (neutral, general)
göra upp sitt schema (draw up, arrange)
lägga schema (often used about making staff rosters/shifts: Chefen lägger schema(t).)

Is precis the same word as English “precise,” and can it mean “exactly”?

Yes. precis means “exact(ly)” in Swedish, and in this sentence it intensifies nu: precis nu = “exactly/right now.” You’ll also see precis used on its own as “exactly”:
— A: Var det svårt? B: Precis!