You know all that stuff you bring into the yard every time you head out there?
Leave that stuff inside. There will be no lawn mowers or hoses in this experience.
Turning the yard into a different experience calls for different tools. What you're looking for are tools that will help you dig deeper, see clearer, see closer and record what you see.
Just a few ideas include a magnifying glass, a small shovel, paper and pen (or perhaps a bound nature journal -- that can be fun), a couple of small jars and maybe a spoon to collect specimens, and some gloves you can use to pick up potentially slithery, slimy, or jagged finds.
Beyond just finding them, it's great to be able to name them. After all, that bird that's been building a nest outside your house for the last week has a genus, a family and a species. That requires a different kind of tool.