Here is how I would go.
To get to the
Disneyland Resort Area, follow the signs for the 55 North freeway/Main street parking. You will start towards reentering the airport, and end up on a bridge that goes over the 405 freeway. This will merge with the off ramp from the 405 to the 55 North. If you miss this and end up at MacArthur Boulevard turn left and heads toward the 405 Freeway. Go over the 405 freeway and the entrance to the 405 North will be on your right hand side. Stay in the right lane as this will go onto the 55 North.
If you have more than one person in the car I would suggest taking the car pool lane. Its much easier, and less traffic. If you are taking the carpool lane, get in the left most lane. When there is an opening to enter the carpool lane get into the carpool lane. Watch for the signs. There will be a bridge to the 5 North Freeway from the carpool lane off to the left. You can either stay in the carpool lane and exit at Disney Way or exit the carpool lane and exit at Katella or Harbor Boulevard.
If you exit from the carpool lane. At Anaheim Boulevard you must go straight (the first light). You can take this street to Harbor, and then turn either left or right. Straight will put you in the Disneyland Parking lot.
If you are not taking the carpool lane on the 55 North, take the 5 North exit (on the right). Stay on the 5 and exit either Katella or Harbor depending on where you are staying.
To get to the Disneyland Parking structure or Disneyland Hotels, exit the 5 North at Harbor Boulevard. Get in the Left-hand Right turn lane (middle lane). At ball road (next light) turn left from the leftmost left turn lane. Stay in the left hand lane as it is hard to get back into this lane. Go up and over the 5 freeway, and turn left at Disneyland Drive. If you are going to Downtown Disney, or the Disneyland Hotels stay in the right-hand left turn lane. For the parking structure you may use either turn lane.
If you took the carpool lane it may be easier to exit from the Disney Way carpool exit, depending on time of day and traffic. To get to DL hotels or Parking structure from here, turn right at Clementine (3rd light after exiting freeway, and the first street you can turn right at), which will turn into Manchester. This street follows alongside the freeway and then turns turning right at the light at Harbor Blvd. You will go up and over the 5 Freeway. To get to Disneyland Hotels turn Left on Ball Road, and then Left again at Disneyland Drive (2nd Light after turning onto Ball).
If you let me know your hotel, I can probably give better directions directly there.