Speed up WordPress using Cache Plugins & Image Compression. Enable G-Zip and you’re good to go! If you’re unfamiliar with the details, lets get started with what you need to focus on.
WP Sweep is great for deleting post revisions and spam comments. These can take up quite a bit of space without you realising. But take care when sweeping other post types such as drafts.
Delete the extra themes & plugins that are not in use/active (bar one) you should always leave one additional theme.
Image Compression services usually charge but you can set your max image size in settings.