I would like to change my daughter's last name from her father's last name to my last name. I will shortly be filling for sole custody and child support. Would like to know the steps I should take for living in the state of Maryland?

Make it all part of the same case. Include a motion for name change as part of your petition for custody and support. But, unless the father agrees, it is not likely to be granted.

What are your grounds for sole custody (physical or legal or both)?

"Q. You may fill out a Petition for Name Change for a minor child if:

The child is one year old or older, and both parents consent to the name change, and then you file the petition in your local court.

If a child is under 12 months, you do not need a court order. The Department of Health and Mental Hygiene can change the name if both parents agree.

If both parents do not consent to the name change, then you may ask the court to decide. The court will look at the “best interest of the child”. The court will look at the following to decide what is in your child’s best interest:

The length of time the father’s name has been used;
The strength of the mother-child relationship;
The need of the child to identify with a new family unit, and
The strength of the father-child relationship.
The court will also consider any additional factors that will help the court decide the best interest of the child/ren.

Important Note about Paternity and Name Change– If your children have their father’s last name, a name change for the child will not change the father’s legal status or responsibility. A name change does not affect the rights and/or duties of either parent. As a parent, you will still have the same obligation for care of the child, pay child support, visit, rights of inheritance, or other legal rights and/or obligations."

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Your options are, have the father agree and sign the paper work, or have it as part of the custody and visit agreement with the father.