Adding a gallery to a Blog Post
1) Login to Squarespace
2) Go to Pages
3) Select Blog
4) Either choose the + to add a new blog or press Settings to update a blog post
5)The post window will open. Roll over the Left side of the white space until the black line appears. Click the Teardrop.
6)Click Grid under gallery options
7) Drag and drop images into the Upload Images box, or click Upload Images to select them from the file listing on your computer. You can select many at a time.
7)Click Design tab in the top Right corner. Select Grid, Aspect Ratio 3:2 Standard, Check Crop Images, choose how many thumbnails per row, and bring "padding around the gridded images" down to 10. Check mark the Lightbox button.
All done! You should see the gallery nicely now!