Questions about work out routine

[DejaVu]

I recently (few weeks ago) started to work out. I am doing 20 situps in the morning and 20 in the afternoon every day. Os this enough to start off? Should I aim to do more eventually? I'm only interedted in abs atm, which is why I'm doing only sip ups. How long should it be before a sixpack starts forming?

[Wakesetter03]

That's not enough. Full stop.
Too get abs, you need to do a variation of ab exercises, sit ups are a good start, but you need to work all abdominal muscles to get a proper six pack.
Another important aspect is cardio - you need to loose any body fat.
Even if you're skinny (I am myself, I have a BMI of 16.5) it is necessary.

Usually I tell people who ask me how long to get abs, look for an improvement in body tone in around five weeks, and proper changes around ten.
But, when people ask me, they're usually following a routine prepared by me, which has been put together by myself, friends and my cousin who PT's me.
The thing about abs is, you need to commit for working for them - then when you get them, you need to maintain your body.

Sit ups (especially such a small amount as 40 per day) won't work.
Maybe after a long time, but don't hold your breath.
If you are going to get a six pack, and work out, do it properly.

[Jdawg91]

To get abs is simple, loose all your belly fat. We all have a 6 pack naturally but its always been covered by a layer of fat. So get jogging,situps are a bonus as well.

[DejaVu]

What other exercises should I do that don't recquire machines? Also, how many sit ups should I aim for?

[Wakesetter03]

What other exercises should I do that don't recquire machines? Also, how many sit ups should I aim for?

Running, Planks, vertical leg crunches, the bicycle exercise, long arm crunches, reverse crunches etc.
It's not hard to find exercises - google it.

[DejaVu]

How many of each should I be aiming to do in a day?

[Wakesetter03]

30 of each, except sit ups and planks.
Do at least 5 planks of 30 seconds each, and at least 60 situps.
This might be too much though, it's been a while since I started doing these exercises, that to me now though wouldn't be an issue.
Run at least 2km (1.2 miles) or for at least 25 minutes.
Start off easy, you want to be pushing yourself, but you need to be able to work out again the next day.

[DejaVu]

I don't have the time to run that distance, anything I can replace it with?