Suunnistamme kartan avulla.

Suunnistamme comes from the verb suunnistaa.

It breaks down like this:

• suunnistaa = to navigate / to do orienteering / to find one’s way
• -mme = we

So suunnistamme means we navigate, we find our way, or in some contexts we are orienteering.

This is the present tense, first person plural.

A few similar forms:

• suunnistan = I navigate
• suunnistat = you navigate
• suunnistaa = he/she/it navigates
• suunnistamme = we navigate
• suunnistatte = you (plural) navigate
• suunnistavat = they navigate

Finnish often does not need a subject pronoun when the verb ending already shows who is doing the action.

Here, -mme already tells you the subject is we.

So:

• Suunnistamme kartan avulla. = We navigate with the help of a map.

You could say Me suunnistamme kartan avulla, but me is usually added only for emphasis, contrast, or clarity.

For example:

• Me suunnistamme, mutta he eksyvät.
  We navigate, but they get lost.

So in your sentence, leaving out me is completely normal.

Because avulla is a postposition, and the word before it usually goes in the genitive.

• kartta = map
• kartan = of a map / map’s / the genitive form of kartta

So:

• kartan avulla = with the help of a map

This is a very common Finnish structure:

• jonkin avulla = with the help of something
• jonkun avulla = with the help of someone

More examples:

• ystävän avulla = with the help of a friend
• tietokoneen avulla = with the help of a computer
• opettajan avulla = with the help of the teacher

So kartan is not random: it is required by avulla.

Avulla is not just a case ending here. It is a full word: a postposition.

A postposition works a bit like a preposition in English, but it comes after the noun instead of before it.

English:

• with the help of a map

Finnish:

• kartan avulla
• literally something like map’s help-by

So the structure is:

• noun in genitive
• • postposition avulla

This is why Finnish uses kartan avulla, not something like a single special case form of kartta.

A useful thing to remember:

• English often uses prepositions before nouns
• Finnish often uses postpositions after nouns

Finnish does not have a normal everyday instrumental case like some languages do, so you usually express this idea with other structures.

For with the help of a map, kartan avulla is one of the most natural ways.

There are also some other possible expressions, depending on nuance:

• Suunnistamme kartalla.
• Suunnistamme kartan kanssa.
• Suunnistamme kartan avulla.

These are not all exactly identical.

1. kartan avulla

This strongly means by using the map as an aid / with the help of the map.
This is the best match for the sentence you gave.

2. kartalla

This can sometimes sound like on the map, so it may be ambiguous depending on context. It is not usually the best choice for using a map to navigate.

3. kartan kanssa

Literally with the map, but this often sounds more like together with the map in a physical sense, not necessarily using it as a tool. It is less idiomatic here.

So kartan avulla is the most natural way to express using a map as an aid.

Suunnistaa can mean a few closely related things:

• to navigate
• to find one’s way
• to orient oneself
• to do orienteering as a sport

The exact meaning depends on context.

For example:

• Suunnistamme metsässä kartan avulla.
  We navigate in the forest using a map.

• Hän suunnistaa hyvin.
  He/She is good at navigating.

• Lapset suunnistavat kilpailussa.
  The children are doing orienteering in a competition.

So the verb has a broader sense than just one fixed English word.

Yes, Finnish word order is fairly flexible, although the neutral order here is very natural:

• Suunnistamme kartan avulla.

This is a straightforward, neutral sentence:
verb + adverbial phrase

You can change the order for emphasis or style:

• Kartan avulla suunnistamme.
• Kartan avulla me suunnistamme.

These are grammatical, but they sound more marked. The fronted phrase kartan avulla gets emphasis, something like:

• It is with the help of a map that we navigate.

So the original sentence is probably the most neutral and natural version unless you want to stress kartan avulla.

Finnish does not have articles like English a/an and the.

So kartta, kartan, and other forms do not directly show whether English would use:

• a map
• the map
• sometimes even just map in a more general sense

The exact interpretation comes from context.

So kartan avulla can mean:

• with the help of a map
• with the help of the map

In many learning examples, English uses a map, because that is the most natural general translation. But Finnish itself does not mark that distinction with an article.

A few useful pronunciation points:

1. Double vowels are long

• suu- in suunnistamme has a long uu
• kartan avulla has short vowels except where written long

2. Double consonants are also longer

• In suunnistamme, the mm is pronounced longer than a single m

3. Stress is normally on the first syllable

Finnish stress usually falls on the first syllable of each word:

• SUUN-nis-tam-me
• KAR-tan
• A-vul-la

A rough English-friendly guide:

• suunnistamme ≈ SOON-nis-tam-meh
• kartan ≈ KAR-tan
• avulla ≈ AH-vool-lah

That said, Finnish pronunciation is much more regular than English spelling, so once you know the sound values, it is very predictable.

Yes — definitely. [genitive + avulla] is a very useful pattern.

It means:

• with the help of ...
• by means of ...
• using ... as an aid

Examples:

• puhelimen avulla = with the help of a phone
• internetin avulla = with the help of the internet
• oppaan avulla = with the help of a guide
• kuvien avulla = with the help of pictures

So it is worth learning avulla as a set pattern:

• minkä avulla? = with the help of what?
• jonkin avulla = with the help of something

This will help you build many useful Finnish sentences naturally.