Шёлк приятный на ощупь, но его лучше стирать вручную.

Because приятный is an adjective agreeing with шёлк.

• шёлк = masculine singular noun
• so the adjective also takes masculine singular form: приятный

So Шёлк приятный... literally means Silk is pleasant...

By contrast:

• приятно is usually an adverb or a predicative word, as in Мне приятно = It is pleasant to me / I’m pleased
• it would not normally directly describe шёлк in this sentence

A more formal/literary alternative would be Шёлк приятен на ощупь, using the short-form adjective приятен.

In Russian, the verb to be is normally omitted in the present tense.

So:

• Шёлк приятный на ощупь = Silk is pleasant to the touch
• literally: Silk pleasant to the touch

This is completely normal in Russian.
If you wanted past or future, then a form of быть would appear:

• Шёлк был приятный на ощупь = The silk was pleasant to the touch
• Шёлк будет приятный на ощупь = The silk will be pleasant to the touch

На ощупь is a fixed expression meaning to the touch or by touch.

So:

• приятный на ощупь = pleasant to the touch

You will often see на ощупь in descriptions of texture:

• мягкий на ощупь = soft to the touch
• грубый на ощупь = rough to the touch

It is best learned as a whole phrase.

Его here means it, referring back to шёлк.

Russian often uses a pronoun to avoid repeating the noun, just like English:

• Шёлк приятный на ощупь, но его лучше стирать вручную.
• Silk is pleasant to the touch, but it is better to wash it by hand.

Even though silk is inanimate, Russian still uses the masculine singular pronoun его because шёлк is a masculine noun.

Here, его is the direct object of стирать.

Russian word order is flexible, and this placement is very natural.

• его лучше стирать вручную literally: it is better to wash by hand
• more naturally: it is better to wash it by hand

Putting его before лучше helps connect it clearly to the previous noun шёлк.

You could also hear:

• но лучше стирать его вручную

That is also understandable, but его лучше стирать вручную is a very common and natural ordering.

This is a very common Russian pattern:

• лучше + infinitive

It means it is better to...

So:

• его лучше стирать вручную = it is better to wash it by hand

This is an impersonal construction. Russian does not need a subject like it here.

Other examples:

• Лучше подождать. = It’s better to wait.
• Лучше не спешить. = It’s better not to hurry.

Стирать is the imperfective verb, and it fits well here because the sentence gives a general recommendation about how silk should be washed.

• стирать = to wash / to launder in a general or repeated sense
• постирать = to wash once, as a completed action

Since this sentence is about proper care instructions, Russian naturally uses the imperfective:

• его лучше стирать вручную = it’s better to wash it by hand

If you were talking about one specific occasion, a perfective verb could make sense in a different sentence.

Вручную means by hand, manually.

So:

• стирать вручную = to wash by hand

This is the standard expression for care instructions, manuals, labels, and recommendations.

Руками literally means with the hands, but in this context вручную is much more natural and idiomatic.

Compare:

• Эту вещь нужно стирать вручную. = This item should be hand-washed.

Yes. That is correct and sounds a bit more formal or bookish.

Compare:

• Шёлк приятный на ощупь — more conversational/descriptive
• Шёлк приятен на ощупь — more formal, concise, slightly literary

Both mean essentially the same thing: Silk is pleasant to the touch.

A learner should mainly recognize both patterns.

Шёлк is pronounced roughly like shyolk, with the stress on ё.

Important points:

• ё is always stressed
• ё is pronounced yo
• so шёлк is not pronounced like шелк with a plain e sound

In many Russian texts, ё is often written as е, but the correct pronunciation is still ё if the word is шёлк.

Because но means but, and it joins two clauses.

Russian, like English, normally puts a comma before но:

• Шёлк приятный на ощупь, но его лучше стирать вручную.

So the comma is standard punctuation here.