How to get ios 7 for my iphone?

I have an iphone 4s and i want to update it to ios 7, but i have no space left on my phone to update it. What do i do? Shall i delete apps? Is it worth it?

It's really good. And once you take a look at you're apps, odds are you will realize that you don't use all of them. I personally deleted about 1, 000 pictures off my phone to get it. And I can say that it was worth it.

The problem is applying the update over the air (OTA) which requires more space on your device, space for the download and then extracting the file.

You are better to to update via iTunes using the USB cable, not only will it be quicker its a slightly safer method in case something goes wrong as you'll have backup you can restore from. Check the link in the source for the downloads of iOS 7.