How can a private pilot prepare for a long cross country flight in an unfamiliar area? TL/DR: What are common preparation tips or techniques for low-hour private pilots planning long cross country flights in unfamiliar territory?



I got my private pilot's license in November 2016 in Hawaii. I've since moved back to the mainland to continue working and flying here. I'm currently in Phoenix and have been checked out for Cessna 172 rentals at a local airfield.  

Over MLK weekend (Jan 14-16) if the weather is nice I hope to fly from Glendale (KGEU) to San Luis Obispo (KSBP) then to Rancho Murieta (KRIU) near Sacramento, and back to Phoenix. My girlfriend plans to come with me and I want to do everything that I can to prep and plan this flight to minimize our risk.

I have about 75 hours total time, mostly in 172s and DA40s and all my cross country time has been on the Hawaiian islands where it is nearly impossible to get lost and there are few airspaces enroute.

I'm very comfortable with VOR navigation but I'm not yet accustomed to the smaller Garmin G430 GPS unit in the Cessna here (I'm spoiled, used to the G1000) so I don't want to stress with the GPS unit.

I'm most concerned with the strength of my pilotage and dead reckoning and whether they are up to the task, especially considering that this will be my first flight in the region. Since VOR is line-of-sight and there more than a few mountains in the region I want to feel confident that I can get us there safely in case the VOR signals aren't being received for the duration.

I have the routes planned, altitudes selected, waypoints and frequencies written down, performance planning and W+B done, etc. and I plan to speak with my local flight instructor to go over all of these materials before the flight.  

In any case, it would be great to hear additional tips/tricks/things to be aware of/mistakes that you made early in your flying career so that I can be as prepared as possible moving forward!
I'm in a similar boat to you and I just did my first XC from KDYL to KDDH a few months ago. Which was the first time I had been to an airport I did not go to during training. It was a lot of fun but here are a few things to consider, 

Get the G430 simulator as Ron mentions. You should always familiarize yourself with all systems in an aircraft before flying it. While you don't need to know the IFR capabilities of the 430 you should understand its VFR functions well. This video covers it well.

If you don't already use it, get ForeFlight or some similar app for your phone/tablet. This will provide you all the charts and calculations you need. Most pilots are using something like this these days but often times it's not allowed during training and many new pilots don't yet have it.   

Use flight following if you can. If your instructor never went over that ask a local CFI about what it is, how to get it, and why you should basically always use it when you can. 

Since it's a new airport for you, watch videos of others landing there to get an idea of what the terrain and airfield looks like. 

If you have, or can get access to a simulator, fly the flight in the simulator using the intended aircraft so you have an idea of time, and basic terrain features en route. 

Perhaps most importantly, this is no time to push your limits both physically and mechanically. Don't depart with "just enough fuel + minimums". Don't make this a "just above VFR minimum weather flight". You will most likely be flying a contiguous leg longer than you have flown yet, understand the human limitations in a situation like this. Understand that the plane has far more endurance than your body and understand when to say "I won't be making the flight today". 

Most importantly, Have FUN!