Tutorial #1 - GIMP
Go from
to
using curves and layers in GIMP. Should be translatable.
Step 1: Open your
image, crop and scale.
Step 2: Take your
base and sharpen.
Step 3: Duplicate this base and set to Screen, opacity 100.0
Step 4: Using Curves(Layers>Colors>Curves) on this layer, I used these settings:
Value: 201/178
Red: 128/158
Green: 127/176
Blue: 128/153
Of course, you should play with these settings, if you want more blue or if you want more red or if you want the image to be lighter. Just make sure to just use these settings as a guideline as it won't work the same on all images.
Step 5: New layer, set to Difference 30.0 and fill with the color 071338
Step 6: New layer, set to Burn 70.0 and fill with the color C6DBF9
Step 7: New layer, set to Burn 30.0 and fill with the color F9C6D9
Step 8: New layer, set to Overlay 60.0 and fill with the color F9E1C6
Step 9: Flatten (and I smoothed the background with the blur tool because it looked weird) and you're done!
Tutorial #2 - PS7
Go from
to
Involves selective coloring, so not translable.
Step 1: Open image, crop and scale.
Step 2: Do not sharpen yet.
Step 3: Duplicate the base and set to screen, 100%
Step 4: New Curves Layer
Red: 129/178
Green: 129/173
Blue: 127/164
Step 5: New Selective Color Layer
Reds
-100/-20/100/100
Yellows
30/-50/-55/50
Greens
-100/-100/100-/25
Neutrals
15/16/16/-5
Blacks
0/0/0/25
Adjust these numbers depending on the picture you are using. Also, it'd be fine to stop here and use this as your finished project, just skip to step 9.
Step 6: New layer, fill with a dark blue (091038) and set to Exclusion at 50%
Step 7: New layer, fill with a light blue (DADEF9) and set to Color Burn at 50%
Step 8: Flatten
Step 9: Duplicate the base and set the opacity at 25-30% and sharpen if you wish. Using curves and selective color can sharpen your base a bit, so you might not even need to sharpen at all.
Step 10: Flatten and you're done!
Like a broken record, I'd just like to say that this is a guide and I intend it to help you play with these settings. So have fun with it and I'd love to see results.