You've decided you wish to start a unit.  Maybe your chapter does not currently have a unit.  Perhaps, you live in an area that has no Chapter but you and possibly others in your area want to create a unit.  You have several options, but all creation follows the same list of requirements.

If you form a Marine Strike Group (MSG), you will be a part of your local STARFLEET Chapter.  You will be responsible for reporting to your Chapter's CO, as well as being responsible for your unit's conduct.  Much like in the Fleet at large, you will find that some in your Chapter may not understand or even like the concept of having a SF Marine Detachment, and it will be your job to help ensure your Strike Group coexists peacefully with the non-Marine elements of the Chapter.

If you form a Marine Exploratory Unit (MEU), you will be part of the region as a whole, answering to a Brigade without an attachment to a Chapter.  You will still be responsible for your unit's conduct, but you will answer directly to the Brigade Staff.

Choosing the Particulars

1. Choose your Individual Branch of Service - There are nine basic choices: Aerospace, Armor, Combat Engineers, Infantry, Maritime Operations, Medical, Mech, Special Operations, and Support.   More information can be found in Orientation under BOS.  An important thing to remember is that choosing a branch will limit some uniform choices and insignia choices for you, but it will have no more effect on your activities than choosing engineering or sciences has on the color of uniform in the Fleet.
2. Choose your Individual Marine Occupational Specialties (MOS) - Your MOS is based on your branch.   Your occupational specialty is your fictional qualifications within a branch.  Your MOS will not affect your activities, but it may affect your uniform and insignia choices.  More information about MOSs can be found in the Orientation section under MOS.
3. Choosing your Unit's Branch Type - Many units also decide on a branch designation for your unit.  If most Marines in your area are of the same branch, it is easy to take that as your unit's branch.  However, there is nothing that states that an individual cannot be of a different branch or MOS.
4. The Numbering of Units within the SFMC - Every unit within the SFMC are identified by a three number designator that falls within a range of numbers assigned to each Brigade.  These numbers are used to identify units as determined by the Commanding Officer Forces Command (COFORCECOM) and then assigned to each Brigade OIC.  Example - MSG 280, MEU 220, etc.
5. Choosing a Unit Nickname - You will discover as you interact with the various units of SFMC, most units have nicknames.  While it can be anything, it should reflect your group's attitude.  Simple rules to follow when creating your nickname:  a)  Is not sexually explicit or suggestive, violent, or derogatory of any ethnic, racial, gender, religious, professional or age group, profane or pornographic, and does not contain nudity; Does not promote alcohol, illegal drugs, tobacco, (or the use of any of the foregoing), any activities that may appear unsafe or dangerous, or any political agenda or message; Is not obscene or offensive and does not endorse any form of hate or hate group; Does not defame, misrepresent, or contain disparaging remarks about STARFLEET, the STARFLEET Marines or its members, or other people or groups; and does not depict, and is not itself in violation of any federal, state, or local law or statute.
6. Moving Forward with Starting a Unit - Once you get to this point, you have a decent idea of the whos and whats of the SFMC, as well as what your unit wants to do.  So what is your next step?  Your first step is contacting your Chapter's Commanding Officer (assuming you aren't the CO), requesting permission to form a strike group aboard your Chapter's vessel.  Your CO's permission will have to be in writing and signed in a letter addressed to COFORCECOM stating you have their permission to move forward with activation. Next, it is off to the Brigade OIC to discuss starting a strike group and to request the paperwork to activate your unit. Your Brigade OIC can mentor you on this process, tell you if your unit number is available and give an initial impression of any nicknames or mottos. If everything makes muster, your Brigade OIC will forward your request, along with that particularly important letter from your chapter commanding officer, to the COFORCECOM for approval and activation.  If there is no Brigade OIC, in the case of those areas without an active brigade, or if you are unable to get a response from your Brigade OIC, contact COFORCECOM directly with your activation request. They will assist you in your task of unit activation.
7. After Your Unit is Activated - HAVE FUN!  No matter what, make certain that you and your unit have fun.   Have socials, game nights, and different types of get togethers to promote socialization and unit cohesion.  Use this cohesion and camaraderie to build your unit's community service aspect, but keep in mind that service while encourage is not a requirement of the SFMC.  If you do take up the service aspect, there are many different types of community service your group can participate in - from volunteering at food pantries to reading at libraries, from volunteering with the VFW and American Legion to cleaning up your community.  It neither has to be large nor expensive, every little bit helps in making a difference.
8. Spread the Word - Get the word out, both to your ship  CO and your Brigade OIC.  Make sure your bi-monthly reports include in as much detail as you can what your unit has been doing - any meetups and the activities participated in; any community service; any conventions; etc.  Also, make certain that your CO has a copy of the reports you send in to the Brigade OIC.  There is an important reason for this, your Chapter's CO is responsible for promotions from enlisted all the way up to 0-5 or Lieutenant Colonel.  Without your report, they will have no knowledge of what your unit's members are doing.  For your Brigade OIC, this allows them to make certain your unit is recognized on a regional and national level, both in awards as well as any promotion above 0-5.  Added to all of this, by spreading the word on social media of what your unit is working on project-wise, there are members of other units who may wish to help and/or join in.

Remember to always ask questions if you do not know an answer and cannot find it.  SFMC members have a rather large amount of resources at their fingertips - from Facebook to Discord, Email to Direct Messaging - allowing members to find answers to almost everything.  Keep in mind, your greatest resource is your Chain of Command.  Always remember you can ask your Brigade Officers and if they don't have the answer, they can find it.

(Material based on Marine Forces Manual 2022 Revision, Section 6, page 18-20)