Instructions
Play "Animal Crossing: City Folk" during spider seasons. Spiders appear at all times of day from March through June and in September. They also appear between 11 p.m. and 8 a.m. in July and August, and between 11 p.m. and 4 p.m. in October.
Buy a net from Tom Nook for 500 bells.
Walk up to a fruit tree. Press the "A" button to shake the tree. If a spider lives in the tree, it will come out of hiding. Keep shaking trees until you find a spider.
Equip the net. Press the "A" button or flick the Wii remote in the spider's direction to catch it.