Je mets un peu de parfum avant de partir.

Because the verb is mettre and with je in the present tense, it becomes je mets.

Present tense of mettre:

• je mets
• tu mets
• il/elle/on met
• nous mettons
• vous mettez
• ils/elles mettent

So mets is the correct je form.

Here, mettre means to put on or to apply.

So je mets du parfum means I put on perfume / I apply perfume.

French often uses mettre for things you put on your body, such as:

• mettre du parfum = to put on perfume
• mettre de la crème = to put on cream
• mettre du rouge à lèvres = to put on lipstick

French often uses broader, more everyday verbs where English might choose a more specific one.

For perfume, French commonly says:

• mettre du parfum

English might say:

• put on perfume
• wear perfume
• apply perfume

So this is just a natural French way to express the idea.

After un peu de, French normally uses de, not du / de la / des.

So:

• un peu de parfum = a little perfume
• un peu d’eau = a little water
• un peu de sucre = a little sugar

Even though parfum is normally something you would often see with a partitive article in other contexts, after un peu, the structure is simply:

un peu de + noun

Because parfum here is being used as an uncountable substance, not as a specific bottle or a specific perfume.

French often uses:

• du parfum = some perfume
• un peu de parfum = a little perfume

So parfum here means the substance in a general sense, not a perfume as an individual product.

Because after avant, when it is followed by a verb in the infinitive, French uses de:

• avant de partir = before leaving
• avant de manger = before eating
• avant de dormir = before sleeping

So the pattern is:

avant de + infinitive

That is the normal grammar.

Because after avant de, French uses the infinitive, not a conjugated verb.

So:

• avant de partir = before leaving

Not:

• avant je pars ❌
• avant de je pars ❌

This is similar to English before leaving, where leaving is not the main conjugated verb of the sentence.

Because partir does not need a reflexive pronoun here. It simply means to leave.

So:

• je pars = I leave
• avant de partir = before leaving

The subject is understood from the main clause je mets..., so French does not need to repeat je or add me.

It can be either, depending on context.

Je mets un peu de parfum avant de partir can mean:

• I’m putting on a little perfume before leaving (right now, in context)
• I put on a little perfume before leaving (habit/routine)

French present tense often covers both simple present and present progressive meanings that English separates.

That is the most natural position here because it tells you when the action happens.

The sentence structure is:

• Je mets = I put on
• un peu de parfum = a little perfume
• avant de partir = before leaving

French often places time expressions like this after the main part of the sentence.

You could also say:

• Avant de partir, je mets un peu de parfum.

That version puts more focus on before leaving.

Both are possible, but they mean slightly different things.

• Je mets du parfum = I put on perfume / I wear perfume
• Je mets un peu de parfum = I put on a little perfume

Un peu specifically emphasizes a small amount.

A common pronunciation is roughly:

zhuh meh-zuhn puh duh par-fuhm ah-vahn duh par-teer

A few useful points:

• Je sounds like zhuh
• mets sounds like meh
• un peu is often pronounced smoothly together
• avant de links naturally in speech
• the final r in partir is pronounced

A more French-style pronunciation in IPA is:

/ʒə mɛ.t‿œ̃ pø də paʁ.fœ̃ a.vɑ̃ də paʁ.tiʁ/

Yes. Parfum is the normal French word for perfume.

Depending on context, French speakers may also say:

• du parfum
• de l’eau de toilette
• de l’eau de parfum

But in a simple everyday sentence, parfum is completely natural.

Yes. This structure is very common:

avant de + infinitive

Examples:

• avant de sortir = before going out
• avant de manger = before eating
• avant de travailler = before working
• avant de dormir = before sleeping

So this sentence is useful as a model:

• Je mets un peu de parfum avant de sortir.
• Je me lave les mains avant de manger.