Most first visits to Hollywood go to Hollywood Boulevard, are mildly disappointing, and end early. The area is better than its most famous block.
Go up, not along
The Hollywood Bowl Overlook and the drive up Mulholland give you the city as it actually looks. Griffith Observatory at dusk is the view everyone has seen and is still worth it — go on a weekday, and be driven, because the parking is genuinely dreadful.
The Boulevard, done briefly
The Chinese Theatre forecourt and the Egyptian are worth twenty minutes. Then leave.
Where the evening actually is
Thai Town for dinner. The Frolic Room or a hotel bar on Highland for a drink. Live music at the Bowl in season, or a smaller room on Vine.
The parking problem
Hollywood is a neighbourhood where parking costs more than the drink and takes longer than the drive. An hourly car for the evening removes it entirely.