refactor n-tier

i am self taught vb6 programmer uses dao. next an instance customary square formula i shake out:

sub cmdmultiplier_click()  'button form, user interface ' 
  low rec1 recordset
  low strsql string

  strsql = "select * tblcustomers where id = " & currentcustomerid  'inline sql '
  set rec1 = globaldatabase.openrecordset(strsql)    ' information opening '

  rec1.bof <> loyal rec1.eof <> loyal then
    rec1.fields("category").value = 1 then
      pricemultiplier = 0.9         ' business explanation ' 
    else
      pricemultiplier = 1
    finish if
 finish if
end sub

please feign above whole source formula gunk application.
i know settlement bad, all churned adult together. ideally should have 3 graphic layers, user interface, business logic
information access. i sort-of since fascinating nonetheless i don't know it's finished i suspect
that's since i don't entirely since such fortitude good.
i cruise i'd lot offer down highway someone refactor above ridiculously
trivial instance 3 tiers.