If you’re using wooden skewers, soak them in water for about 20 minutes to prevent burning on the grill. Preheat your grill to medium-high heat while you prep the veggies.
Slice the sausage into bite-sized rounds or chunks that will thread easily onto skewers. Cut peppers and squash into similarly sized pieces, about 1-inch squares, and cut red onion into wedges or chunks that will align with the other ingredients.
In a small bowl, whisk together olive oil, minced garlic, lemon juice, oregano, paprika, and a pinch of salt and pepper. Reserve a small portion for brushing later.
Toss the sausage pieces and vegetables in the marinade, coating evenly. Let sit for 5–10 minutes while the grill comes to temp; this quick rest helps flavors begin to meld.
Thread the sausage and vegetables onto skewers in an alternating pattern (sausage, pepper, onion, zucchini, tomato, repeat). If using metal skewers, you can rest them directly on hot grates; if using wooden skewers, ensure they’ve been prepped and rounded ends are out of the way.
Place the skewers on the grill. Cook for 8–12 minutes, turning every 2–3 minutes, until the vegetables are tender-crisp and the sausage is heated through and slightly charred on the edges. Brush with the reserved glaze midway through cooking for extra shine.
Remove from heat and let rest for 2–3 minutes. This helps the juices rediscover their balance after the grill heat. Sprinkle with chopped parsley if desired before serving.