Не то чтобы шляпа мне совсем не подходит, но в кепке и сандалиях мне удобнее гулять летом.

Не то чтобы is a common Russian expression meaning something like:

• It’s not that...
• Not exactly that...
• It’s not really the case that...

It often introduces a soft correction or a nuance.
So here:

Не то чтобы шляпа мне совсем не подходит, но...

means:

It’s not that a hat doesn’t suit me at all, but...

The speaker is softening the statement. They are not strongly rejecting the hat; they are just saying that comfort is the more important issue.

Yes, подходить can mean to approach, but it also has another very common meaning:

• to suit
• to fit
• to be appropriate for

In this sentence, шляпа мне подходит means:

• A hat suits me
• A hat looks good on me
• A hat works for me

So шляпа мне совсем не подходит means a hat doesn’t suit me at all.

Совсем adds emphasis. In negative sentences, it often means:

• at all
• completely
• in no way

So:

• не подходит = doesn’t suit
• совсем не подходит = doesn’t suit at all

Russian commonly combines совсем with negation this way. It is not a logical double negative in the English sense; it is just normal Russian emphasis.

Мне is the dative case of я (I). In Russian, verbs like подходить often use the person affected in the dative:

• Мне подходит = It suits me
• literally: To me it is suitable

So:

шляпа мне совсем не подходит
= a hat doesn’t suit me at all

Russian often expresses this idea with the dative where English uses a direct object like me.

Because it belongs to two different parts of the sentence:

1. шляпа мне совсем не подходит
   = the hat doesn’t suit me at all

2. мне удобнее гулять летом
   = it is more comfortable for me to walk in summer

In both places, мне means for me / to me, but it goes with different expressions:

• подходить кому = to suit someone
• кому удобнее + infinitive = it is more comfortable for someone to...

So the repetition is perfectly natural.

Удобнее is the comparative form of удобно:

• удобно = comfortable / convenient
• удобнее = more comfortable / more convenient

The speaker is comparing two options:

• wearing a шляпа (hat)
• wearing a кепка и сандалии (cap and sandals)

So the meaning is:

but it’s more comfortable for me to walk in summer in a cap and sandals

Even though the first option is not terrible, the second one is better from the point of view of comfort.

This is a very common Russian pattern:

• кому + удобнее / легче / труднее / лучше + infinitive

Examples:

• Мне удобнее работать дома. = It’s more convenient for me to work at home.
• Ему легче читать по-русски. = It’s easier for him to read in Russian.

So:

мне удобнее гулять
means
it is more comfortable for me to walk / go for walks

Гулять usually means:

• to walk
• to go for a walk
• to stroll
• sometimes to spend time outdoors casually

Here it means something like to go walking or to take walks.

It fits well because the sentence is about what is comfortable to wear while walking in summer.

A verb like идти would mean a specific act of going somewhere, and ходить would emphasize repeated going on foot more generally. Гулять is the most natural choice for a relaxed outdoor-walking idea.

Yes, в usually means in, but in Russian it is also commonly used to describe what someone is wearing:

• в пальто = in a coat
• в шляпе = in a hat
• в сапогах = in boots

So:

• в кепке = wearing a cap
• в сандалиях = wearing sandals

This is very natural Russian. English usually prefers in a cap and sandals or simply wearing a cap and sandals.

They are both in the prepositional case because they follow в in a stative/descriptive meaning:

• в кепке — prepositional singular
• в сандалиях — prepositional plural

This is not motion into something. It is a description of appearance or clothing:

• Он в куртке. = He is wearing a jacket.
• Она в шляпе. = She is wearing a hat.

So here the speaker is describing the outfit that feels more comfortable for walking.

Because Russian often uses the instrumental case to express seasons and certain time expressions.

• летом = in summer
• зимой = in winter
• осенью = in autumn
• весной = in spring

So:

мне удобнее гулять летом
= it’s more comfortable for me to walk in summer

This is a very common pattern and should be learned as standard usage.

Yes:

• шляпа = hat, usually with a brim, often more formal or stylish
• кепка = cap, more casual and practical

That contrast matters in the sentence. A шляпа may suit the speaker aesthetically, but a кепка feels more comfortable and practical for summer walks, especially together with сандалии.

Yes, Russian word order is flexible, and this sentence could be rearranged. For example:

• Летом мне удобнее гулять в кепке и сандалиях.
• Мне летом удобнее гулять в кепке и сандалиях.

The original order:

...но в кепке и сандалиях мне удобнее гулять летом

puts early emphasis on the clothes themselves: in a cap and sandals.

So the word order helps highlight the contrast with шляпа.

Because но means but, and it joins two contrasting parts of the sentence. In Russian, a comma is normally used before но.

So the structure is:

• Не то чтобы... , но...
• It’s not that..., but...

The comma marks the contrast between the softened first idea and the real point that follows.

It sounds natural and conversational, but still perfectly correct standard Russian.

What makes it sound natural:

• Не то чтобы... но... is a very common spoken pattern for expressing nuance.
• мне удобнее is an everyday way to talk about comfort or preference.
• в кепке и сандалиях sounds like ordinary spoken description of clothing.

So this is the kind of sentence a native speaker could easily say in normal conversation.