Teaching students to match is an essential language skill. It builds vocabulary and comprehension and is a prerequisite to many higher-order math skills like classification and sorting. It's especially important for emergent communication skills. Students using alternative and assistive communication devices (AAC) need to understand that the picture they are pointing to represents an actual object.
Begin teaching matching at a concrete level using actual objects. One of my favorite, functional ways to do this is by matching socks. You can also match various manipulatives, action figures that are especially motivating, paint swatches, or bowls and cups that stack together. If you're looking for more concrete matching activities, I have linked lots of them on this Amazon board.
After the student understands how to match objects to objects, try matching pictures to objects. Gather small toys or objects and take pictures of each item. You can also use a symbol program, like Symbol Stix or Smarty Symbols, if you don't want real photos.
Next, move on to match pictures to pictures. I love using Match It! tasks for this. These tasks come with three different matching levels, errorless, identical matching, and non-identical matching. I like to start with errorless matching activities so that students understand where to place the pictures and how to complete the task. Next, I introduce a Match It! task by presenting one matching card at a time. As students get more proficient with the skill, I give them more than one card to match at a time, until they are finally able to complete the task independently. I like to start with matching identical pictures first, then move to matching non-identical pictures, and finally to matching words to pictures.
I love creating binder activities or cut and paste activities with them. Binder tasks take more prep upfront but they last forever! You can even turn them into file folder activities. Try them out and let me know how it goes!