Learn French: Il vaut mieux changer souvent le pansement. - It is better to change the bandage often.

The expression il vaut mieux (it is better) is directly followed by an infinitive verb. Unlike many other impersonal expressions you have learned (such as il est important de or il est temps de), it never takes de or à.

Does il vaut mieux mean the exact same thing as c'est mieux de?

They are very close, but il vaut mieux gives a stronger sense of advice, much like "you had better" or "it is highly advisable to". C'est mieux de is slightly more casual and states a general preference.

What verb does vaut come from?

It comes from the irregular verb valoir, which means "to be worth". The literal translation of il vaut mieux is "it is worth better". When giving advice like this, it is an impersonal expression, meaning it only ever uses the pronoun il (it).

Why is souvent placed directly after changer instead of at the end of the sentence?

In French, short or common adverbs (like souvent, bien, toujours) usually go directly after the verb they modify, even if that verb is an infinitive. So it is much more natural to say changer souvent le pansement than putting souvent at the very end like we do in English.