What are you doing before and after this walk?
Knowing what you plan to do before and after this walk will make deciding which direction to walk easier.
Which end do you want to start vs which end do you need to start?
Some people just book the huts ASAP and then only much later look at how to get there. Book your transport and huts at the same time otherwise, you might get stuck.
What Hut accommodation is still available?
With huts being booked out months in advance, sometimes you then have no choice but to walk in a certain direction and then plan accordingly. Routeburn Falls and Lake MacKenzie are the first to get fully booked which then means that no matter which end you start you will have at least one long day.
If you have to miss one of those huts, then miss out the Routeburn Falls.(Flats hut is only an extra 1.5hr)
For Campers, Lake MacKenzie has only 9 sites. So Book that first.
How are you getting to the start and How are you leaving from the end?
From Trail end to Trail end it is 350km by road.
What Transport Options are still available?
Having your car relocated is becoming more popular each year, as hikers are seeing the true value of this service. As are the Bus services. So coordinate with your transport service provider when booking hut tickets. With the majority of hikers starting from the RTB Roadend means that the transport services are quickly being booked out in this direction. So one of the advantages of starting from the Divide is that it is easier to get transport from Te Anau to the Divide and then from the RTB Roadend to Queenstown, than it is from Queenstown to the RTB Roadend and The Divide to Te Anau.
What time are you planning on starting and finishing?
When starting have you allowed yourself enough time to get to your nights destination and still enjoy the walk. When finishing have you allowed yourself enough time to get there without rushing. If you plan on catching a Bus, then you can finish earlier but never later.
How long do you want to take vs How long do you need to take?
The track times are a guide only, If you are new to hiking and carrying a heavy pack then you may need extra time. The weather can either speed you up or slow you down depending on how you like it.
Do you have the fitness to really do what you have planned?
Most new hikers tend to over estimate their fitness and skill levels. Carrying a heavy pack when you're not used to it will quickly drain any energy you thought you had. Are you used to 4-8hrs of continuous exercise? If you're planning on doing the Routeburn in a day average time is 10-12hrs with only short rests along the way.
Are you Mentally prepared for the journey?
Even more important than physical fitness is your Mental Skills and Attitude. When you are physically pushed to your limit then it will be your mental abilities which will keep you on track.