Step 1

Endgame damage over time bow crafting guide (~6-7 ex cost)

Buy 6-Link lvl 82 Maraketh Bow ~20c
Step 2
Alt spamm until you have T1 damage over time multi ~200 alts needed
Step 3
If it's the only mod - move to step 4
If not - use Orb of Annulment to remove Prefix (50% chance to remove Prefix)
If you remove Suffix - move to step 2
Step 4
When your only mod on the Bow is Damage over time Multiplier - use regal orb
Step 5
Remove mod you have got after using regal ( if it's a suffix - use orb of Annulment. If you delete damage over time - move to step 2)
If it's a prefix you can use 'Suffixes can not be change' benchcraft + orb of scorching to guarantee removing a prefix or use orb of Annulment(50%)
Step 6
Use crafting bench to add Multicraft (2 ex) + cannot roll attack modifiers (1 ex)
Step 7
Use Exalted orb to add '+1 to level of socketed gems'
Step 8
Use Hunter Exalted Orb to add 'Chaos damage over time'
Step 9
Use crafting bench to re-add Multicraft > +2 to level of socketed support gems >
Damage over time multiplier (2 ex + 2 ex + 5c)
You would need to use bench crafts to make this bow, if you do not have them - use TFT channel to buy them