The parade is best viewed from the southern side of Colorado Blvd. That way the sun will be behind you.
If you want to be in the front row along Colorado Blvd, you'll need to arrive in the late afternoon or early evening the night before. By midnight, most of the front row will be occupied.
On the morning of the parade, you might be able to find a position in the front row along Sierra Madre Blvd, but the view and parade experience is much better on Colorado Blvd.
A few hours before the parade starts, the sidewalk will be packed. It's difficult to walk around. But as soon as the parade starts, most everyone will move closer to the street, and then there's more room. That means if you're tall enough to see over other peoples' heads, and you arrive late, you can always find a place to stand after the parade begins.
You can park at or near one of MTA's Gold Line parking lots, and ride the train to the parade viewing area. That way you won't need to search for a parking space near the parade (very difficult), and you won't have to deal with traffic congestion immediately after the parade. The walk to the parade route is two to four blocks from the MTA terminal, depending on where you get off the train.
Reserved grandstand seating can be purchased at face value from Sharp Seating, which is the Official Grandstand Seating Company for the Rose Parade. If they are sold out, you could try a ticket broker or eBay, although the price will be marked up. face value prices range from $40 to $75. The best seats aer near the beginning of the parade route and those tickets sell out first.
Float viewing at Victory Park after the parade - The Showcase of Floats is a popular event that sells out quickly and no advance tickets are available, so proceed to the viewing area as soon as possible if you want to go.
Overnight "camping" on the sidewalk is allowed only on December 31.
A permanent position on the sidewalk may be secured along the parade route beginning at noon on December 31. There is a blue line painted on the street about six feet from the curb. This is also known as the "honor line." All people, blankets, chairs, and other items must remain on the sidewalk until 11 PM, when spectators may move to the honor line.
Small, professionally manufactured barbeques that are elevated one foot or more off the ground are allowed on the parade route.
Minors (under the age of 18) who are on the parade route between 10 PM and 5 AM must be under the supervision of adults.
Dress for cold weather to avoid hypothermia.
It will be very difficult to sleep, as there will be quite a bit of noise and activity until at least 3 AM.