You tie it essentially the same way you tie regular boot/shoe laces - then, you adjust the bow for 'looks' and length.
If you use a ribbon,- make sure you use a silk gros-grain one - ask about those at a fabric shop - and hem the ends neatly.
You 'may' find it gratifying to know that they had pre-tied ties available during the era - just as they do today, for bow ties.
A tie 'made' as a tie will display better, because of the heavier construction - while one made from ribbon stock will fall limp.
Vaya,
Scouts Out!