How to Solo Index Guide

First of all, get a good weapon that can kill enemies, It can be [Vermisplicer] or [Tenet Cycron]. You wont have any ammo issues with these weapons and they deal very good damage.
Celestial Twin is the Damage dealer here. It has Auto Aim with unlimited ammo + it deals more damage than you.

You dont need a very good [Wukong] build for this, in fact, with just a little strength and no eclipse, roar or subsumed ability, you can still easily go for 2-3 rounds of solo index with a standard weapon and [Wukong]. Depending on how fast your weapon kills though, your speed will differ.

Stay at the same area shown in the image below. Its on the enemy side and under the platform, safe from any bullets.

The enemies spawn at places that you dont look towards, so just look towards the yellow marker and the enemies will keep spawnin from your right, making the points dropped from enemies grouping in one place. Let all the banking job be done by the specters.

If there are too many points on the ground, you can pick them and score just so you wont be wasting time. You can use your operator to score so that your clone wont leave the area to keep killing the enemies around it while you come back.

To not be affected by Inactivity Penalty, just switch to transferance by pressing 5 from time to time. You can be very confortable as you dont need to do much. You can read your book, watch your favorite tv series, talk to your friends etc while also solo farming high index fast.

With this method, you can solo high index with ease, while it is easy, it is also fast as you will be able to finish 4 rounds of index in 14-16 minutes. Mind that this is Solo, so you wont need to waste your time looking for squad-mates.

Abilities

Roar is a good option for your Celestial Twin with this build. But you need to know that you need to cast your roar to your twin for your twin to be able to get the buff. If only you have the roar buff, your twin wont have it. If your twin dies while it had the buff, you can respawn it but it will no longer have the roar buff and you need to rebuff it.

[Total Eclipse] with a decent range is the best option as it will give your clone AND the specters the buff they need all the time.
Cloud Walker is a very good ability. It will make you and your clone invinsible on cast, remove all status effects inflicted on you and heal you and your clone while moving.
Also, when you get out of the cloud, your clone will be spawned in front of you, making it convenient when you want to buff it or relocate it.

You can use Defy on higher level enemies from 5th round and so. It will help you survive a little more.

Zenurik is essential for the energy as you will be recasting your Eclipse from time to time.

Also not to forget, [Wukong] has an amazing passive that lets you escape death 3 times per mission, while also giving buffs after you escape from death.

SPECIAL NOTE: The video is old and the spot I used was also the old spot. The new spot is much more safer and faster.

Special thanks to Basi#1056 & Nezarec for the AFK SPOT. Much better than my previous spot. Safer and easier to collect points.