To receive all 131 Jiggies you will need to do the following:
Complete all 97 challenges with at least a Jiggy rating. (97)
Complete 96/97 challenges with a T.T. rating. (24)
Buy all of Jolly Dodger's Jiggies. (5)
Find all the Tampered Switches. (5)
Jiggy Ratings: If you're having trouble on a mission, pause the game and select "View Leaderboards" under the second section, then find and select the mission name and hit Y to view one of the top 10 replays. Some of them will even have their blueprints there to download so you can use their same vehicle. If you don't have all the parts, fill in the missing sections with whatever you can. If you're missing something important like the weapons, try to return more crates in Showdown Town or complete more missions to either get bonuses from Mumbo or unlock more parts to buy from Humba.
T.T. Ratings: The most common challenges that people can't manage a T.T. on are either "Saucer of Peril Returns" or "Flower Shower Power" in the Terranium of Terror so aim to complete one of those and ignore the other. Again, watch replays and download blueprints if you're having trouble.
Jolly Dodger: He can be found either underneath Klungo's Arcade or somewhere on the beach to the left or right. You will need 375 notes total to buy all five of his Jiggies.
Tampered Switches: The five switches are found in the following locations:
Underneath the big lighthouse. Find one of the big alcoves, the location is on the right side of it, only big enough for Banjo to walk through.
On top of L.O.G. Factory, next to the pole you climb for the "Head for Heights" achievement.
Underwater below Klungo's Arcade.
On a balcony on the outside of Uptown. Directly to the right of the Uptown entrance is a drainpipe to climb to reach the roofs. Find where the balcony is and drop off the side onto it.
Behind the L.O.G. Factory is a tunnel you can enter (requires Scube Gear). Once inside, take a path off to the right and up onto dry land, then exit your vehicle and walk up a small tunnel similar to the first switch in the back of the lighthouse.
This solution from another sight helped me immensely. The biggest help was finding out that you can modify L.O.G.'s vehicles for the challenges where your forced to use a specific vehicle. At the beginning just hop out and tap red to reconfigure the parts.