From Central or Wynyard in the city, any bus with the number between 184 and 190 will go through Warriewood. The express buses (e.g. E87, E88) might not stop at Warriewood (those that don't should say 'First Stop Mona Vale' on them), though all limited stops buses (e.g. L90) should stop outside the McDonald's. Ask the driver to be sure.
If you're just trying to get to Warriewood beach from Mona Vale or from Narrabeen or points further south to Manly, the 155 takes a detour from Pittwater Road to take the picturesque Old Pittwater Road up to Warriewood headland. And also, Sangmo is the bestest.
If you want to get to Chatswood, you need to take an early bus one suburb south to Mona Vale and get off, cross the road and take the L60 bus to Chatswood. Note that this bus only runs on weekdays in peak hour to ferry people to and from work. If you absolutely have to get to Chatswood at another time using public transport, you would have to take a bus to the city (which takes an hour or so) and then catch the train to Chatswood (a further 20-30 minutes).
Warriewood beach is one of the most picturesque on the peninsula and is ideal for swimming. It is a relatively small beach and headlands on either side mean it is protected from the wind and the surf is usually calmer and less choppy than nearby Mona Vale beach. Old Pittwater Road, which leads to Warriewood beach, climbs up from Narrabeen so that the approach to Warriewood is from the level of the headland. The beach itself is reached by walking down a trail from the top, or driving down to a small car park right next to the beach.
On the southern headland of Warriewood beach there is a walking trail that affords lovely views of the Northern Beaches and leads to North Narrabeen beach.
Warriewood is also home to the 'Blowhole', a popular spot for young daredevils to jump from the headland into the ocean. The blowhole has been featured on Australian soap show Home and Away , which is mostly filmed further north at Palm Beach. It is not recommended jumping off this blowhole, as it took the life of a 19-year-old man in February 2006.
The headland between Warriewood and Mona Vale beaches is a popular spot for paragliders - but be warned, sudden unexpected winds can be a major problem for inexperienced 'jumpers' - at least 3 major incidents in 2008 alone!
Away from the beach, there is a relatively new and modern cinema complex just off Pittwater Road behind the McDonald's. On the other side of Pittwater Road there is a golf driving range and two themed putt-putt golf 'courses' - caves and shipwreck.
The best place to pick up supplies or do a bit of shopping in the area is Centro Warriewood, on Jackson Rd, which leads off Pittwater Road on the non-beach side. At Centro Warriewood you will find a K-Mart, a Coles & Woolworths supermarket, a food court and a range of other specialty stores..
If you're at the beach, there is a cafe at the South end of the beach, open mainly during the summer and week-ends. On the road above the beach, there's a typical Australian burger place (Sunrise Cafe) on the corner of the row of shops. Hamburgers are delicious like McDonalds have shown us.
Along the line of shops there is a Thai restaurant open for lunches and evening meals, a second cafe and an Austrian Restaurant (mainly evenings and week-ends).
Away from the beach across Pittwater Road, there is a McDonald's, a Hogsbreath Cafe and a restaurant in the cinema complex
There is a Youth Hostel at Collaroy, and a privately run hostel at Avalon, and a number of B&Bs along the way. The renovated Sands Hotel at Narrabeen also has accommodation. You could also rent a unit or house privately, e.g. through searching internet real estate sites or local newspapers. For those who are roughing it, North Narrabeen hosts a sizeable caravan park.