Using Drop Down Lists in Userform to Hide Sheets

[ob1kin0bi]

Let's say I have Sheet1-Sheet6. I also have combobox1 (with item 1, 2, & 3 as the list items) & combobox 2 (with items 1 & 2 as the list items).

If combobox1 = 1 & combobox2 = 1 then
hide Sheets 2,3,4,5,6
if combobox1 = 1 & combobox2 = 2 then
hide Sheets 1,2,4,5,6
If combobox1 = 1 & combobox2 = 3 then
hide sheets 1,2,3,4,6
If combobox1 = 2 & combobox2 = 1 then
hide sheets 1,3,4,5,6
If combobox1 = 2 & combobox2 = 2 then
hide sheets 1,2,3,5,6
If combobox1 = 2 & combobox2 = 3 then
hide sheets 1,2,3,4,5

I would like to also make both of these combo boxes required fields and to default text to say 'Select One...'

Any help is greatly appreciated, thank you!