I've never used GIMP to create prints.
I always just let Windows take care of this.
Using whatever software comes bundled with my printer.
Is a good way of keeping things simple.

Consider using an online printing service.
This is another good way of taking the hassle out of making prints.

Having the image prepared for printing.
Is also a big part of how the image appears once it's printed.

* * *

Here are a few things to keep in mind,
when preparing images for printing.

Monitor Calibration
Type of Print
Sharpening the Image (if required)
Soft/Hard Proofing (before actual printing)
Resizing the Image
Image Resolution
Creating a Border
Color Profile/Color Space
DPI Settings (Dot’s per inch)