WordPress has a built-in gallery feature that can be used to add a gallery of images to any post or page. It is really simple to use.

First open an existing post/page of your choice , or create a new post. Then  upload all the images you would like to see in the gallery on this page/post. To do this, click the “Add an Image” icon to upload a selection of gallery images.

After you have uploaded an image, do not click “Insert into post” as you would if you are adding a single image, but when you have typed in the details for the image, click “Save all changes“. The browse for the next image. Repeat this until you have all the images for your gallery uploaded.

You will notice as you load the images that a tab appears at the top of the pane called “Gallery“.

Click this tab to see all the images you have loaded ready for this page/post gallery.

Now scroll down to the foot of this section and you will see the Gallery Settings.  Choose you how you would like the images ordering, and how many columns you want your gallery to have. on this page/post. Typically you might have 3 on a website which has a 3 column layout, 4 on a website with 2 column layout, and 6 if your website is full width. Once you have selected the settings, click Update Gallery settings.

You will now see the camera icon appear on the page/post where your gallery will sit.

Click Publish or Update for your page (on the top-right as usual) to make the gallery live.

Visit the page on the live site and  you will see that thumbnails have been automatically generated to create a gallery of images.

When you click on any thumbnail the larger image will be activated.  Ideally you will have a lightbox effect to allow the larger image to pop-up over the page and to permit scrolling through all the larger images.

This just needs a simple plugin. If your designer has not already done this for you, then it is very easy to install.

Go to Plugins (on the left-hand bar), click “Add New” and then “Search plugins” to find a lightbox plugin.

jQuery Lightbox for Native Galleries is very simple to set up. Install it, activate it and  select the theme you want to use (this is the styling for the pop-up box) and you are done!