Learn Hardcore Malay: Selepas mandi, saya rasa lebih cergas dan sedia untuk kerja. - After bathing, I feel more energetic and ready for work.

Selepas mandi literally is after bathe/bathing.
Malay doesn’t need an explicit -ing ending; mandi can function as:
- a verb: Saya mandi. – I bathe / I take a shower.
- a kind of verbal noun: Selepas mandi – After bathing / after a shower.

You could add a subject if you want to be explicit:

Selepas saya mandi, saya rasa… – After I shower, I feel…

But it’s very natural and common to just say selepas mandi when it’s obvious that it’s your shower.

What’s the difference between selepas and lepas? Could I also say sesudah?

All three are related, but they differ slightly in formality and usage:

selepas – standard, neutral, a bit more formal; common in writing and careful speech.
lepas – more informal/colloquial, very common in everyday conversation.
sesudah – also standard, sometimes feels a bit more formal or literary, but still normal.

In your sentence:

Selepas mandi, saya rasa… – perfectly standard.
Lepas mandi, saya rasa… – more casual, everyday speech.
Sesudah mandi, saya rasa… – also correct; slightly more formal or bookish in tone.

All three would be understood as After showering, I feel…

Does mandi mean a bath or a shower?

Mandi is a general verb meaning to bathe / to wash the body. It doesn’t strictly distinguish between a bath and a shower the way English does.

Context decides which English word you choose:

In many homes where people usually shower, mandi is best translated as to take a shower.
In other contexts it might be to take a bath.

If you really want to be specific, you can add a noun:

mandi dalam tab – bathe in a bathtub
mandi shower – (colloquial) shower-bathe, i.e. take a shower

But in most everyday contexts, mandi alone is enough.

What exactly does saya rasa mean here? Is it I feel or I think?

Rasa literally means to feel or to taste, but it also extends to emotions and opinions. So:

Saya rasa lebih cergas – I feel more energetic.

Depending on context, saya rasa can mean:

I physically/emotionally feel…
- Saya rasa penat. – I feel tired.
- Saya rasa gembira. – I feel happy.
I think / I suppose… (giving an opinion)
- Saya rasa dia betul. – I think he/she is right.

In your sentence, because it’s followed by an adjective about physical state (lebih cergas), the natural reading is I feel more energetic.

How is tense shown here? How do I know if this means I felt, I feel, or I will feel?

Malay doesn’t change the verb form for tense the way English does. The basic forms:

saya rasa – I feel / I felt / I will feel (depends on context)

Time is usually shown by context or by adding time words:

Tadi selepas mandi, saya rasa lebih cergas.
Earlier, after showering, I felt more energetic.
Setiap kali selepas mandi, saya rasa lebih cergas.
Every time after showering, I feel more energetic.
Nanti selepas mandi, saya akan rasa lebih cergas.
Later after I shower, I will feel more energetic.

In your standalone sentence, without extra context, English speakers would normally translate it in the present:
After showering, I feel more energetic and ready for work.

What does lebih do in lebih cergas? How is it different from sangat cergas?

Lebih is a comparative marker meaning more.

cergas – energetic
lebih cergas – more energetic

So saya rasa lebih cergas suggests a comparison: more energetic than before, or more energetic than usual.

Compare:

sangat cergas – very energetic (high degree, not necessarily comparing).
lebih cergas – more energetic (compared to some previous state or standard).

Common patterns:

lebih + adjective – more + adjective
- lebih besar – bigger
- lebih cepat – faster
paling + adjective – most + adjective
- paling besar – biggest

So here, lebih cergas = more energetic.

Does lebih apply to both cergas and sedia, or just cergas?

Grammatically, lebih directly modifies cergas:

lebih cergas dan sedia
= more energetic and ready

So if you’re being strict, lebih only attaches to cergas.

However, semantically, the whole phrase is describing how you feel after showering, and many listeners will understand it as: more energetic, and (also) ready for work. If you want to be explicit that both are “more so than before”, you could say:

lebih cergas dan lebih bersedia untuk kerja – more energetic and more ready for work.

But the original sentence is fully natural and idiomatic.

What’s the difference between sedia and bersedia? Why use sedia here?

Both are related, but they’re used slightly differently.

sedia – an adjective meaning ready / prepared.
- Saya sedia. – I’m ready.
bersedia – a verb (or verb-like) meaning to be ready / to get ready / to prepare oneself.
- Saya sedang bersedia. – I am getting ready / preparing myself.
- Saya sudah bersedia. – I am already ready / I have prepared myself.

In sedia untuk kerja, sedia is used as a simple state: ready for work.

You could say:

Saya rasa lebih cergas dan bersedia untuk kerja.

That is also correct and common, and it emphasises that you are in a state of being prepared. The version with sedia is a bit shorter and slightly more adjective-like in tone, but both are natural.

Why is it untuk kerja instead of untuk bekerja? What’s the difference between kerja and bekerja?

Kerja can be a noun or a verb depending on context:

Noun: work, job, task
- Saya ada banyak kerja. – I have a lot of work.
Verb (informal/colloquial): to work
- Saya kerja di Kuala Lumpur. – I work in Kuala Lumpur.

Bekerja is more clearly a verb: to work (more standard/formal):

Saya bekerja di Kuala Lumpur. – I work in Kuala Lumpur. (more standard)

In your sentence:

sedia untuk kerja – ready for work (treating kerja as a noun).
sedia untuk bekerja – ready to work (treating bekerja as a verb).

Both are acceptable, but the nuance is slightly different:

untuk kerja – sounds like for work (the activity/job).
untuk bekerja – emphasizes the action to work.

In everyday speech, sedia untuk kerja is very natural.

Is the word order Selepas mandi, saya rasa … fixed, or can I say Saya rasa … selepas mandi?

The word order is flexible. In Malay, time expressions can go at the beginning or later in the sentence.

Both are fine:

Selepas mandi, saya rasa lebih cergas dan sedia untuk kerja.
After showering, I feel more energetic and ready for work.
Saya rasa lebih cergas dan sedia untuk kerja selepas mandi.
I feel more energetic and ready for work after showering.

Putting Selepas mandi at the beginning emphasises the time/condition first, similar to English. Putting it at the end feels a bit more casual and conversational. Both are natural.