How do you use the previous day's value area?

A volume profile is a sideways histogram. Fat prices are where a lot of business happened. Skinny prices are where almost nobody traded. The value area is the band where most of the session's volume printed. The edges of that band are the value area high and the value area low.

Use the previous day's value as the primary reference. Above yesterday's value leans bullish because price is accepting a higher fair area. Below it leans bearish. Inside it, expect two-way trade until something changes.

This is the condition. It is not a prediction of the close. It is a statement about what kind of day you are allowed to trade.

Sources: Volume profile beginner guide · Best volume profile strategy