The best tip I can give you on taking a better picture, no matter what camera you're using, is to use natural light to light your pictures. Never, ever use the on camera flash. It never looks good. I know the temptation is there when it's midnight, the sun is gone and you want to get that post up with a picture. But don't do it! Your photos will instantly improve if you make use of natural light (especially a diffused sunlight without harsh shadows).
How to take a photo with a "blurred" background:
If you have a camera that allows you to shoot manual settings (shutter speed, aperture, ISO etc.), turn your aperture down as low as you can (e.g. f 1.8, f 3.6 etc.). And if you're using a DSLR extend the lens as far as it will go (e.g. extend an 18-55mm to 55mm). This will increase the "blur", but you may have to back up to capture the whole image.
If you're using a point and shoot, put the camera on the portrait setting. Then place your subject as far as you can from your background. This will isolate your stack of books (or whatever your object is) and blur out the background. Depending on your camera's aperture range, you will get a somewhat blurred background.
If all that fails and your camera just won't do what you want, try finding a cleaner background. It's much simpler to recompose your image than get frustrated. The best camera is the one you have. Besides, simple backgrounds are generally better backgrounds.
(P.S. You can also add blur in the editing stage using the focal blur tool on picmonkey.com)
But say you want to put the text over the subject? That's when you need to use the "veil" method.
White text lined with back:
No matter what the background, you will be able to read this. The word "this?" in the first picture uses this method. It's a huge difference between the plain text and this method.
This works in a similar way to the white-on-black method, but is a bit more subtle. It's my favourite way of making sure a text is readable.
This is where you drop a darker (or lighter, depending on the picture) tint over the picture. This is definitely the best way to make the text readable, but it also obscures the picture behind it.
Each of these methods has their benefits, and ultimately is a stylistic choice a blogger has to make. Sometimes, it's just a matter of using a different colour for the text, but if the background has too many colours, it's important to use a "veil", so you can read it. Picmonkey.com is a great resource for creating these veils, even if you have to add a drop shadow manually.
Always pick something that you can read. I know that handwritten fonts are trendy (and awesome), but I've seen a few that are really hard to read. You can also experiment with mixing different fonts and emphasize different words with larger font sizes (e.g. the pictures above). If you do use different fonts, I recommend making separate text boxes; it make's it so much easier to get them to lay right.
Some of my favourite downloaded from the internet fonts are: Bebas Neue (the font used for "Formatting text") and Great Vibes (the font I used in my Jan. Book Haul post pictures).
You can also opt for an actual handwritten font. You can write out your title and just put it your picture.
The commonly used text orientations are center and right aligned (see above pictures). Those are great, but it's always interesting to try aligning the text to the left or flipping the text on its side. You can also try overlapping text (see first picture), but make sure it's all still readable. When using two different fonts, I like to "fit" them together (e.g. "fitting" the swoop of the "J" over the "R" in the second picture).There's so many different ways to arrange a text on the picture, so experiment and see what works for you!
Now you should be ready to create your own picture header!
I know that this is a long post, but I felt like I had a lot to share with you. I hope you found it helpful! I tried to make all of these tips accessible, no matter what software/camera you have. You can use picmonkey.com (a free, online, editing service) for almost all of these tips.
Let me know what you like to do for your header picture or if you even bother with a header picture in the comments!