It is always preferable to have a Deacon or a Priest bless any object.
with that said:
Blessing of Homes by Laity:
(Click Here) EWTN: Blessings by Laity
(emphasis is mine

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EWTN Catholic Q&A
Blessings by Laity
Question from Diane Gaudin on 05-25-2005:
I do not mean to supplant any blessings that should be said by a priest. But is it licit to bless the doors and rooms in my home and business with Holy Water and the sign of the cross or use blessed salt in the same manner. Also, my granddaughter who is not baptised is being raised by my daughter, who left the church to marry a protestant. I regularly have my granddaughter make the sign of the cross with holy water when we take her to church and I make the sign of the cross on her forehead and ask God to bless her and keep her safe. Is what I am doing correct?
Answer by Rev. Mark J. Gantley, JCL on 05-25-2005:
There isn’t any point in someone who is not baptized blessing themselves with holy water on the way into church. The purpose and meaning of this custom is to remind the person of his or her baptism. In this case, the child is reminder herself of a past event that never occurred.
People may bless their own homes with holy water. This should be done according to the ritual provided in the Book of Blessing, following the directions for a lay person. (There are different rubrics that apply for this to be done by a priest or deacon.)
There is no provision for the blessing of offices or places of business by a lay person.
I am familiar with the practice of blessed salt being added to holy water by a priest or deacon. However, I don’t know what you are doing with it.
Be careful that your little practices are not bordering on superstition.
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Use of Holy water in the house
Use of Holy water in the house
Question from Jim R. on 07-03-2012:
Hello Father,
I was uncertain where to post this question. I’ve sprinkled my home liberally with Holy water only recently learning that I should not do this. Now that objects normally disposed of after use (paper, pens, bags, bulletins,etc) have possibly been touched by the water, am I required to keep everything even though I had no intention of sacramentalizing non religious objects?
Answer by Fr. John Echert on 07-04-2012:
Not sure who told you not to sprinkle your home with Holy Water but I see no problem with this. I assume your object is to sanctify your home and since you are not a priest these items do not become sacramentals, so they may be used and disposed of as would normally be done. Think about the consequences of sprinkling rites in the churches if anything touched by water was so sacred it could never be thrown away–you would not even be able to spend “holy money” in your purses and wallets, if the assumption is that they are now sacramentals (they would only be fit for the collection basket
So I would feel free to use Holy Water in your home, not intending to bless every item as such but to sanctify the home.
Thanks, Jim
Father Echert
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as for the proper form… get the rubrics from the book of blessings…
as for blessing a car or a dog etc… Father has told us to use a simple form…
the “Glory Be…”, “Lord we ask you to watch over all that use this and keep them safe from all harm”, and sprinkle the water on the item.
Obviously not the same as a priest’s blessing (which is partially the point) but none the less caries our intent.
There are rubrics for the Laity in the book of blessings for other such things… one can find this online and in any good Catholic book store.
It’s encouraged to have a holy water font by your doors (even so far as in every room). Husbands and wives can bless each other and their children etc… A lot of this is covered in the CCC and has been covered in other threads here on CA.
Consuming holy water… I’ve heard of it; however, personally I don’t see the point. One would not receive the graces from consuming the sacramental to any greater degree than if one merely blesses oneself with it.
As for blessing other sacramentals… that must be done by someone with proper holy orders.