I'm writing up some technical documents which describe steps to complete an operation. One of the opening paragraph sentences is similar to:
To wash your car you will first need a sponge.
It was suggested that this sentence should be broken up with a comma. For example:
To wash your car, you will first need a sponge.
Is the latter example a correct use of a comma?
The latter example is a correct use of a comma. You are delineating the introductory part of the sentence and pointing it toward the subject "you," who needs to get a sponge first.
While it is generally acceptable to drop commas from short sentences of about 10 words or fewer, I would recommend keeping the comma in formal / technical writing.
You can also think about it like this: when speaking the sentence aloud, you naturally create a small pause between car and you. That's a clue that you may need a comma.
