something you might wanna add is a flood protection.
Lets say on your channel, there is 100 nicknames/users
Bam! .net .split
50% of them leaves.
Bam. Net-merge (a ".net .split" fixing itself)

50 users joins your room. you send 150 /say, you quit in (Excess flood)

Try to make sure they are not rejoining from a netsplit, or put a %var that will make the script do nothing if exceeded . with a /return or /halt.

here is an example with your code.

on *:join:#: {
  if (%noflood.example. [ $+ [ $chan ] ] >= 2) { halt }
  inc -u3 %noflood.example. [ $+ [ $chan ] ] 1
  if ($nick == $nick) {
    timer 1 3 Describe $chan humps $nick 
    timer 1 5 say Ohhaithar $nick
    timer 1 7 say how YOU doin?!? ;)
  }
}

Please keep in mind, that i really don't think small lines of useless codes like this one should be on hawkee.
There should be a minimum of ~50 lines to be valid...

But the method is there, learn from it, and use it in everything. (with different %variable.names.

Here is what i would do. (if i would be in a life or death situation)

on *:join:#: {
  if (%noflood.example. [ $+ [ $chan ] ] >= 2) { halt }
  inc -u3 %noflood.example. [ $+ [ $chan ] ] 1
    Describe $chan humps $nick 
    .notice $nick Welcome on $chan $+($nick,!) This is your $iif($+(%n.j.,$chan) == 0,First, $+(%n.j.,$chan)) Visit with us. Have fun :)
  }
}

Welcome on hawkee :)