Spune-mi încă o dată cum să iau medicamentul.

Mi is the unstressed pronoun meaning to me. In an affirmative command, Romanian usually attaches this kind of pronoun to the verb with a hyphen.

So:

• spune = tell
• mi = to me
• spune-mi = tell me

This is very normal Romanian word order for commands.

Yes. Spune-mi is the singular informal form, used with one person you address as tu.

If you want to be polite or if you are speaking to more than one person, you would usually say:

• Spuneți-mi încă o dată cum să iau medicamentul.

A more polite version could also include vă rog:

• Vă rog, spuneți-mi încă o dată cum să iau medicamentul.

Încă o dată means once more, one more time, or simply again.

Literally, it is something like:

• încă = still / yet / another
• o dată = one time

So the whole phrase means one more time.

Here it is written as two words because o is the word for one / a, and dată means time/occasion.

So încă o dată is literally another one time.

Learners sometimes notice odată written as one word elsewhere, but in this sentence o dată is the standard spelling because it is the numeral/article o plus the noun dată.

Romanian often uses question word + să + verb where English uses how to..., what to..., when to..., and so on.

So:

• cum să iau medicamentul = how to take the medicine
• more literally: how I should take the medicine

Romanian does not normally use the infinitive in exactly the same way English does here. That is why cum să iau sounds natural.

Iau is the 1st person singular form of the verb a lua, which means to take.

So:

• a lua = to take
• iau = I take
• să iau = that I take / for me to take / I should take, depending on context

In this sentence, să iau is the subjunctive construction after cum.

Because Romanian often drops subject pronouns when they are not needed.

The ending of the verb already tells you who the subject is:

• iau = I take

So eu is unnecessary unless you want emphasis or contrast.

For example:

• cum să iau medicamentul = how I should take the medicine
• cum să iau eu medicamentul would add emphasis to I

Because Romanian usually puts the definite article at the end of the noun.

So:

• medicament = medicine / a medicine
• medicamentul = the medicine

This sentence is referring to a specific medicine already known from the context, so the definite form is used.

Romanian word order is fairly flexible, but this version is very natural and clear:

• Spune-mi încă o dată cum să iau medicamentul.

The placement of încă o dată is important because it clearly modifies spune-mi: tell me again.

If you move it, the sentence can become less clear. For example:

• Spune-mi cum să iau medicamentul încă o dată

This could sound awkward or potentially suggest taking the medicine one more time, rather than telling me one more time.

So the original order is the safest and most natural one.

A rough guide:

• încă ≈ uhn-kuh
• iau ≈ yow (one syllable)

A couple of useful sound notes:

• ă sounds like the a in about
• î has no exact English equivalent, but it is a central vowel pronounced with the tongue high in the mouth

So even if your pronunciation is not perfect yet, aiming for yow for iau and a short central vowel in încă will get you close.