Solution by Bomberman913, corrected by Vea, last correct, last mission and images by Xargo

cause this quest has multiple missions, this guide will be long

i wrote this guide AFTER i finished the quest, so i dont know when advancements are, or what your 
actually suppose to say
if i ever feel liek it/have time, ill get pictures

Mission 1
1) find kevin between cyc bridge and dwarf bridge
2) say hi-->mission-->yes-->yes-->yes*forgot how many times*
3) Go to thais
4) Take the boat to Carlin
5) Go to the magic carpet in femur hills
6) Go to edron from there
7) Take the boat to venore
8) Walk to Kazordoon
9) Take the steamboat to cormaya
10) Go to the small boat, to go to edron, and take the carpet to femur hills
11) walk to kevin, and say hi-->mission-->yes

Mission 2
1) Get a crowbar(venore/edron)
2) Go to folda
3) Go north west to the mountain
4) go to the top, and use the crowbar on the mailbox
5) Go to kevin, and say hi-->mission-->yes

Mission 3
1) Go to venore
2) Go to the room below the depot
3) find "A strange guy"
4) Say hi-->hat-->hat-->hat*couple more times, till he summons rabbits*-->bill
5) Go to kevin, and say hi-->mission-->advancement-->yes-->mission-->yes
*get postal hat*

Mission 4
1) Go to either a goblin/skeleton spawn, and colect 20 bones
2) Go to kevin, and say hi-->mission-->all-->yes-->yes

Mission 5
1) Open the blinky door to the right
2) Open the chest
3) DO NOT OPEN THE PRESENT
4) Go to fibula
5) Go to Dermot, and say hi-->present-->yes
6) Go to kevin, and say hi-->mission-->yes

Mission 6
1) Go to venore
2) go find hugo south east from the depot
3) say hi-->new dress pattern*say a few times i think, and say till he says he will send a mail to
kevin*
4) Go to kevin, and say hi-->new dress pattern-->yes

Mission 7
1) Go to kazordoon
2) Find Talphion
3) say hi-->new dress pattern*couple times till he admits he did outfits before*
4) Go to kevin, and say hi-->new dress pattern-->yes

Mission 8
1) Go to the Queen in Carlin
2) say Hello Queen-->uniforms-->yes
3) Go to kevin, and say hi-->new dress pattern-->yes

Mission 9
1) Go get moldy cheese, a banana skin and a piece of fur
2) Go to thais castle
3) talk to Noodles
4) say sniff moldy cheese-->Do you like that?
5) say sniff banana skin-->Do you like that?
6) say sniff piece of fur-->Do you like that?
7) Go to kevin, and say hi-->new dress pattern-->yes

Mission 10
1) Go back to Hugo
2) say hi-->new dress pattern-->yes
3) Go to kevin, and say hi-->mission-->yes

Mission 11
1) Take 12 arrows, grapes and 5 gp with you.
2) Go to Edron and say measurements to the NCP that's selling parcels.
3) Go to Carlin and say measurements to the NCP that's selling parcels. You need 12 arrows here.
4) Go to Kazordoon and say measurements to the NCP that's selling parcels. You have to talk to
the armory seller for the parcel NCP's measurements here.
5) Go to Thais and say measurements to the NCP that's selling parcels.
6) Go to Venore and say measurements to the NCP that's selling parcels. You need the grapes
here.
7) Go to Ab'Dendriel and say measurements to the NCP that's selling parcels. You need the 5 gp
here.

Mission 12
1) Go to thais troll caves(east of thais)
2) Open the shovel hole
3) go down, and go to the right
4) on the branch, go north
5) on the 2nd branch, go east
6) go up the ladder, and open the closed door to your left
7) open the corpse for the horn
8) Go to kevin, and say hi-->mission-->advancement-->yes-->mission-->yes
*get postal horn*

Mission 13
1) Open the blinky door to the left now
2) Open the chest(make sure you have 500cap)
3) Go to Vega
4) Go west
5) USE the bag on the mailbox
6) Go to kevin, and say hi-->mission-->yes

Mission 14
1) Go to mintwallin
2) say hi to markin, LOOK OUT its summons much of archers, mages and guards if you say "hi" for
the first time. Try to lure them to a door so you can kill them one for one!
3) say hi-->letter-->yes
4) Go to kevin, and say hi-->mission-->advancement-->yes
*use mailboxes in dangerous places*