How to Insert NextGEN Gallery in WordPress

Install NextGEN
1. Login to your WordPress dashboard and click on the 'Plugins' link in the left-hand menu. Click on 'Add New' and then type 'NextGEN' into the search form.
2. Click on the 'Install Now' link under 'NextGEN Gallery,' then click 'OK' when WordPress asks if you want to install the plugin.

3. Wait for the plugin to install itself, then click on the 'Activate' link to turn on the plugin.
Create a Gallery
4. Click on 'Gallery' at the bottom of the left-hand menu in WordPress's dashboard. This expands the 'Gallery' menu, and offers a number of links to gallery setup and options pages. Click on the 'Add Gallery / Images' link to start creating your first gallery.
5. Type a name for your new gallery, then click the blue 'Add gallery' button. Click on 'browse' and highlight the files you want to add to this gallery. You can select multiple files at once.
6. Select the gallery you are uploading to from the select box. Click on 'Upload images' to upload the images. Some pop-ups appear as the plugin uploads the files and creates the thumbnails.
Insert a Gallery
7. Click on 'posts' or 'pages' on the left-hand sidebar in the WordPress dashboard, depending on which content type you want to edit. Both posts and pages are compatible with NextGEN galleries.
8. Click on the 'edit' link below the title of the post or page where you are inserting the gallery. On the right-hand side of the editor are two tabs marked 'Visual' and 'HTML.' Click on the 'Visual' tab to make sure you are using the visual editor rather than the HTML editor.
9. Find the place in the post or page's text where you want to add the gallery. Type the following shortcode: [nggallery id=your-gallery-name]. The gallery name must match the name you gave your gallery, so a gallery titled 'new-gallery' will have a shortcode of [nggallery id=new-gallery]. Click the blue 'update' button to save the changes.
10. Visit the edited post or page on your WordPress website. The gallery shows where you placed the shortcode. By default, a link to 'Show as slideshow' appears as thumbnails. Click on a thumbnail to see a larger version of the image as an overlay on your site.