[Literally]

Here are a couple ideas:
Before starting your walk insert the small black plug. Walk to the woods and after finding the first secluded spot immediately switch to the large red plug for the remainder of your walk.

Find a good spot where you have a bit of room to move around without immediately risking being seen. Strip down completely nude and leave your clothes in a pile at your feet. Grab your small pink dildo and close your eyes, spin around for 15 second and toss it into the distance, continue spinning with your eyes closed for 25 more seconds.
Now you must find your toy naked. Begin searching on your hands and knees, for every minute that passes without you finding the toy you must edge once. After finding the toy you may use it to finish an orgasm. Return to your clothes and get dressed.

Have fun, stay safe, and I'm looking forward to hearing/seeing how it went.