We often use 'do' when we don't say exactly what activity we're talking about:

What do you want to do?

She did something really strange.

He's so lazy. He just sits around all day, doing nothing.

We often use 'do' when we're talking about work and jobs:

What do I do? I'm a teacher.

Have you done your homework?

He's doing the ironing just now.

We often use 'do …ing' when we're talking about activities that take a certain amount of time or that are repeated (like jobs or hobbies):

He wants to do some reading at the weekend.

She's gone to the supermarket to do the shopping.

He does the crossword every morning.

an attempt
a trial, an effort at doing something
Don't give up on your homework so easily. At least make an attempt at it.
He made a brave attempt at running the marathon but didn't manage to finish it.

an effort
the activity needed to achieve something
She always makes an effort when we go to visit her. She bakes a cake or something nice like that.
Make an effort and at least try to look busy when the boss comes in today!

a mess
something that looks untidy
You've made a real mess in the kitchen! I hope you're going to tidy it up.
He made a right mess of the report. He'll have to write the whole thing again.

an exception
someone or something that is not treated according to the usual rules
We don't usually allow visitors but because you've travelled so far we'll make an exception.
The teacher made an exception and let me hand in my essay late.

your hair/make-up
hairstyle, lipstick and cosmetics
I need to do my hair before we go out.
She always does her make-up before leaving the house.

your best
the most effort
It doesn't matter if you fail or not, just as long as you do your best.
She did her best in the competition and won the gold medal.

50 miles per hour (mph)/ kilometres per hour (kph)
speed something can travel at
The car can do up to 200 kph
The new motorbike can do more than 175 miles per hour

a favour
a kind action
Would you mind doing me a favour and posting this letter for me?
Do us a favour, will you and close the door?

a ton of
a lot of

You've been a million miles away
You haven't been concentrating on what you should have been concentrating on because you have been thinking about something else

knuckle down (informal)
start working or studying hard

gave me a good talking to
spoke angrily to me because I had done something wrong

gruesome
unpleasant or shocking