In case you didn’t know, Twitter just released new profile enhancements for your profile and header photos. Since things can get dry, I try to change header photos every once in a while to help keep things fresh. So I figured I’d create a mini-tutorial for you on how you can help use Lightroom to set up some presets and make it easier to save the images at the sizes you need. And even if you don’t use Twitter or change header images much, I think you’ll pick up a couple of tips here anyway for cropping and saving images with presets. Here goes:
Header Photo
Let’s start with the header photo because this is the one I change most often. First, Twitter recommends you size the photo to 1500 x 500 pixels. If you just export a JPEG at 1500×500, Lightroom will automatically do a center-crop on the image and it’ll be hard for you to really judge what it’ll look like in Twitter. Sure, you can upload a photo and use their cropping tool, but it’s just more fun in Lightroom
Anyway, the first thing you should do is crop your photo. So go to the Develop module and choose the Crop tool. Then go to the Aspect list and choose Custom. Enter 3 x 1 and click OK (it’s the same aspect as 1500 x 500). Now you’ve got a cool little crop preset for visualizing what your photos would look like in the header.

Next, go to File > Export. Under Image Sizing, change the width and height settings to 1500 x 500 pixels. Then under File Settings make sure you choose JPEG and sRGB. And if you really want to take it up a notch, click the Add button at the bottom left corner to add this as a preset. Now it’ll be available to you under the menu File > Export with Preset > Twitter Header.

Profile Photo
This one is pretty easy. Twitter recommends sizing the photo to 400 x 400 pixels. If you’re in the Develop module using the Crop tool, just choose the 1×1 preset that’s already there. If you want to save the JPEG and/or preset, just follow the steps above to do the same thing.
I know not everyone uses Twitter or will save images for it that often, but hopefully you got a couple of little cropping and exporting tricks here along the way. See ya!