"Grounding and centering" means a lot of different things to a lot of different people, so you may have to try different things - or even combine different things to find what works best for you.
In general terms, when you feel sluggish, drained, or as you describe 'in a perpetual daze,' you are dealing with energy either building up that needs to be released, or draining out and needs to be replenished - in either situation you need to find what is your sense of
equilibrium.
The simplest G&S exercise is to go outside and walk barefoot through some grass, visualizing all stresses and negativity draining out through the soles of your feet into the Earth where they are neutralized. OR you sit quietly in a chair and visualize roots growing through your feet going down through the floor or floors, thru the bsement, pavement, etc., and reaching down into the Earth. There the energy and negativity grounds itself out and your 'roots' bring you refreshment, calming, and peace. OR - take a shower and visualize the excess energy and negativity washing off you like dirt, washing down the drain and away from you, leaving you cleaned and refreshed. I am sure other posters will also add their favorite G & S practice for you.
The other idea you may work with is that you are
attracting excess energy to you, or something is
pulling your energy out of you ~ and need to create a 'shield' to protect you. You can do many things to 'erect' a shield around you from the simple burning of incense, to lighting several candles around you, to building psychic shields and structures such as the LBRP ("Lesser Banishing Ritual of the Pentagram"). All of these require you to visualise either a sphere of protection, a cloud of protection, or actual mental walls to contain your energy or deflect outside energy. Try the simplest ones first.
Anyone have more suggestions?