По утрам она быстро красится: сначала поправляет брови, а потом красит ресницы тушью.

По утрам means in the mornings / every morning / mornings in general. It describes a habitual repeated time.

• утром = in the morning (often one occasion, or just a general time of day)
• по утрам = in the mornings, every morning, morning after morning

So here по утрам fits because the sentence describes her usual routine.

Grammatically, утрам is the dative plural of утро, because this expression uses:

• по + dative for repeated times

Similar patterns:

• по вечерам = in the evenings
• по ночам = at night / nights
• по выходным = on weekends

Here краситься means to put on makeup / to do one’s makeup.

The -ся ending often gives the idea that the action is directed toward oneself. So:

• красить = to paint, color, dye, apply color to something
• краситься = to make oneself up, to put on makeup

In this sentence, она быстро красится does not literally mean she paints herself in an English-sounding way. It is the normal Russian way to say she does her makeup quickly.

Be careful: depending on context, краситься can also mean things like to dye one’s hair or to wear/apply cosmetics more generally.

They are related, but used differently:

• она красится = she is putting on makeup / doing her makeup
  This is a general, reflexive action.

• красит ресницы = she colors/paints her eyelashes, meaning she applies mascara to her eyelashes
  This is a specific action on an object.

So the sentence works like this:

1. она быстро красится = a broad summary
2. Then the colon introduces the details:
   • сначала поправляет брови
   • а потом красит ресницы тушью

So красится is the overall activity, while красит ресницы is one concrete step within it.

They are imperfective because the sentence describes a routine / habitual action, not one completed event.

Russian often uses the imperfective aspect for things that happen regularly:

• По утрам она быстро красится...
• Every morning she does her makeup quickly...

This is not about one single morning when she finished everything. It is about what she usually does.

If you wanted to describe one completed sequence on one specific occasion, perfective forms might be more likely in the right context. But here the focus is her normal morning habit, so imperfective is natural.

Поправляет here means something like:

• tidies up
• fixes
• adjusts
• touches up

So поправляет брови is not literally corrects her eyebrows in a strange English sense. In a makeup context, it means she neatens or shapes them, or touches them up.

The verb поправлять is very flexible in Russian. It can mean:

• to straighten
• to adjust
• to fix
• to put right
• to touch up

Here it fits cosmetic grooming very naturally.

Because in Russian, possessive words like her, his, my are often omitted when the owner is obvious from context, especially with:

• body parts
• clothing
• personal items
• actions done to oneself

So:

• поправляет брови
• красит ресницы

naturally mean:

• she fixes her eyebrows
• she paints her eyelashes

Russian does not need её here, because we already know the subject is она.

If you did add её, it could sound more emphatic or contrastive in some contexts, but it is not necessary in this sentence.

Тушью is the instrumental singular of тушь.

Here it shows the means/instrument used to do the action:

• красит ресницы тушью = she colors her eyelashes with mascara

This is a very common use of the instrumental case in Russian:

• писать ручкой = to write with a pen
• резать ножом = to cut with a knife
• красить кистью = to paint with a brush

So the pattern is:

• красить что? → ресницы
• чем? → тушью

Also, тушь in this context means mascara. In other contexts it can also mean ink.

Because Russian usually talks about eyelashes as a plural set, just like English often does.

• ресница = one eyelash
• ресницы = eyelashes

When someone applies mascara, they normally apply it to the lashes as a group, so красит ресницы is the natural expression.

The same idea applies to брови:

• бровь = eyebrow
• брови = eyebrows

Since people usually groom both eyebrows and their eyelashes as sets, the plural is expected here.

Both are possible, but а потом is very natural here because it links the two steps in a sequence:

• сначала поправляет брови, а потом красит ресницы тушью

This structure is extremely common in Russian:

• сначала ..., а потом ... = first ..., and then ...

Here а does not have to mean a strong contrast like but. It often simply helps organize the flow of actions and mark the next stage.

So in this sentence:

• сначала = first
• а потом = and then / then

The colon is used because the second part explains or breaks down the first part.

The structure is basically:

• She does her makeup quickly: first she fixes her eyebrows, then she applies mascara to her eyelashes.

So the first clause gives the general statement:

• По утрам она быстро красится

Then the colon introduces the details of how that happens:

• сначала поправляет брови, а потом красит ресницы тушью

This is very natural punctuation in Russian, just as it is in English.

Yes. Быстро simply means quickly.

It modifies красится:

• она быстро красится = she does her makeup quickly

Its position is also natural. Russian word order is flexible, but this version sounds neutral and straightforward.

You could move words around for emphasis in other contexts, but here the sentence is standard and idiomatic.

Yes, it is a normal and understandable way to say it.

Literally, it is:

• to color/paint the eyelashes with mascara

In natural English we usually say:

• to put on mascara
• to apply mascara

Russian often expresses this more literally through the action done to the eyelashes:

• красить ресницы тушью

So even if the structure looks different from English, it is perfectly natural Russian.