The best way to unleash the creativity of a young child is to simply set out some supplies and materials and let them explore. One of Everett's favorite activities is cutting, so I often set out materials for him to cut up like scraps of fabric, string and ribbon.
In order to capture a product (none of which he really cares about in the moment) that we can enjoy later, I help him with gluing down some of what he has cut. Of course, seeing the finished product hanging up later does instill within him a sense of pride and a value for beautiful things.
I do most of the glue squeezing, but he chooses where the glue goes. I find the easiest way is to blob out the glue in several different locations and allow him to set materials into the glue at his pace and choosing. If you have a little one that doesn't like glue on his fingers (even Everett want to immediately wipe it off) keep a wet washcloth handy or use a popscicle stick or pair of tweezers to press materials into the glue.
This activity keeps Everett quite busy for a long while. If you have an older toddler you want to do an activity like this with, perhaps focus more on just playing with the materials, scooping them in and out of the box, comparing the different textures, placing fabric onto felt and practicing cutting together (I started using scissors with Everett about age 2). Do remember to keep your talk short and simple. The best way for little ones to explore is without much thinking done for them!