Workflow when using a "Today" perspective?

Hi Guys,
Previously I used perspectives to group contexts together into a view of things that I can do at a certain place.
“Computer”, “Anywhere”, “Office” all go into the perspective “Office”.

I’ve been fairly successful with this so far but lately the amount of tasks that can be done in each context increased by a bit. I now have multiple projects inside “Computer” that all show up.
I have a rough prioritisation in my head and follow that when doing the tasks in that perspective.

I recently read that a lot of people have a “Today” perspective which collects flagged and due tasks that are schedule for that day. I’ve been wondering how you guys are filing what should be done today. Do you take these tasks at the beginning of the day out of the perspective that is appropriate? Say if I’m in my office perspective, do I pick the Today tasks from that?

What when contexts change?
In the morning I was at Home and flagged things for the day that I wanted to do at home. Now I’m in the office and flagged some more things. All of that shows up inside “Today” and not just whatever is appropriate for the given context which increases noise.

I’d love to hear some thoughts.

The first thing that I work on are all of my overdue and due tasks. I created a Due perspectives that shows due soon tasks grouped by due date. The overdue/due today tasks are located at the top and have a red status circle. The due soon tasks comes next with a yellow status circle. The rest have the standard gray status circle.

I try to work on the topmost items first (overdue and due today). These are the highest priority. Then work on some due soon (yellow status circle) so that I can get ahead of things as they come down the line.

Optionally, I will go to the flagged perspective and work on flagged tasks. At the beginning of each week, I look for available tasks and flag a small handful of tasks that don’t not have a due date but are items that I would focus on for the next week. These are important for me to flag and it shows up in the flagged perspective. I will go to the flagged perspective as a medium priority. I won’t work on the flagged tasks until I have gotten my overdue/due today tasks done.

Some folks like to show due and flagged to combine the due perspective and flagged perspective. But I would suggest having it sorted or grouped by due date. This will make all due tasks go to the top of the list.

I think that the most important part of workflow is not in choosing what should be done today, but in hiding all the things that can’t or won’t.

Placing projects you know you aren’t going to act on now on hold and deferring tasks you know you’re not going to move on is, I think, vital to keep the list of available options at a reviewable minimum.

In this way, much like @wilsonng, I review available tasks in the morning and flag the ones I will do that day (based on GTD constraints of what contexts I will be in, time required, energy available, and relative value).