Set up your CameraWhether you are using a digital SLR or a smartphone, set your camera to at least 5Megapixels (2592x1552), preferably 8Megapixels (3264x1952) or more.
Set up your ShotUnless you have a specific requirement for "portrait" (tall) images, you should take your photographs with a "landscape" orientation. It is surprising how many people forget this when using their smartphones.
Leave more room around the edges than you think you need, keeping the subject central - the edges can be cropped and often edited (to remove objects or repeat scenery) as required, without stretching to increase the width. This is especially important if using wide banner header images on your website. Also, try to keep horizons horizontal - photographs can have tilt correction during editing if there is sufficient space around the main image.
Cropping and EditingIf you are cropping or editing the image yourself, remember to store the original full size photograph and work on a copy - give the copy a meaningful name rather than pic-01 (see below). You can then use the original to generate several different shapes and sizes at any time.
Images for WebsitesWhen your website designer asks for images, offer to send a copy of the original photograph or the specific size that is requested. If you are uploading images yourself to update your WordPress website, check the maximum size necessary - uploading several images at 5600pixels wide will slow down the website's performance - usually a 2000-ish pixel width is adequate.
Before you upload images, ensure that they have meaningful titles, e.g. pink trainers rather than img-01, and add a descriptive Alt-title or Alt-text when using images on your website or blog, which helps search engines to index them properly.
Thanks to Professional Solutions (website design-and-build) #Herts for inspiring this post.