We told you to turn off Photo Stream a few slides ago, but 1GB of Photo Stream images might be worth the sacrifice for being able to easily back up the photos you take on your iPhone. Go to Settings > Photos and turn My Photo Stream on using the slider.
Now, as long as you have Wi-Fi access, every photo you take will appear in the Photo Stream on your iPhone and on any other devices you’ve set up to receive it. (Note that when you turn it on the phone will upload the last 1,000 images, which is likely to take a few minutes.)
Now that the photos you’re taking are appearing in your Photo Stream, you can delete them from your Camera Roll. They will still be available to download on your other devices (at least until you’ve taken another 1,000 photos, pushing that one out of your allocated iCloud storage).
When you want to download the image to your Mac, open the Photos app there and click on iCloud. You may need to wait for a moment while the Photo Stream updates itself, depending on how often you access the photo library on your Mac. Once the image you want appears, right-click and choose Import.
You can also save the image to your iPad by tapping Select picking that image, and then tapping Add To and selecting an Album to add it to.
You can delete all the photos from your phone now without worrying about them being lost forever.
How to back up iPhone photos in another article.