1: Off season
Going in the less-popular season often means getting cheaper prices as not many people visit these areas at that specific time of the year, which often leads to bargain rates! But in turn what that also sometimes means is less fellow tourists in the area and you can sometimes find yourself being the only car out there! In most southern African countries off-season refers to the summer months (higher rainfall months) which provide a more lush vegetation which can be stunning for wildlife photography.
2: Go to lesser known places
Not only are you more likely to encounter less other tourists, but these places offer cheaper prices. And who knows - you might very well discover some hidden gems off the beaten track! Be adventurous...
3: Don't be afraid to ask
Went traveling through southern Africa and getting to a new area, it is always a good idea to ask a local or someone who knows the area about places to eat or camp; which routes are safe and accessible or most scenic and - for wildlife areas: what sightings they have had. A chat from driver seat to driver seat goes a long way and most people will be happy to help and point you in the right direction.
Which leads to the next tip:
4: leave it flexible
Its a good idea to leave some parts of your intended itinerary flexible and not planned, so that when a local has given you a tip about an amazing campsite you have the freedom to go and try it out. Make it up as you go!
5: Invest in good maps
I cannot stress this point enough. Most people these days have got (or have access too) a smart phone or tablet. There are multiple offline maps that include many of these adventurous roads in some of the most remote places in Africa, so it is well worth your time to download more than one of these to take the stress out of African Navigation. Let your phone do the work so that you can focus on finding those animals! Check out Maps.me and Tracks4Africa.
6: Get a local guide to travel with you
Many campsites are community run in remote areas and often they have an option of taking a local along with you to guide your around the area. Often this individual knows how to get you to those amazing and often secret spots that are just breathtaking. And if you are really looking for someone with a wealth of knowledge to travel with you, invest in a private guide to escort you for some of, or the entire duration of the trip!