Here is some additional guidance (this is mostly project management guidance for risk mitigation and to prevent scope/job creep):
Should you perform an assessment of the entire building and draw up project specs? Create an entire field assessment and field survey of the entire office where you are doing this project. You should then make sure the employer/client understands that you will need to draft detailed project specifications for this work and explain any fact they don't know. The worst employer or client will be the one that thinks you are a snob and know everything without telling them. They may perceives themselves as computer ignoramuses. It is your job to relieve this problem (as much as humanly possible and within certain reasonable boundaries), by
informing them of the scope of the project. More importantly, if you do not know the scope of the project, you may become the victim of a never ending project.
Do you already have supplies? Now that you have some idea of how you are going to do this, be certain supplies and technologies have already been supplied or mandated, authorized, paid for, or otherwise arranged, and ensure that they will work with a proposal that you will create or have already created and given to your employer/client for this project.
Why all of this detail? By conducting a field assessment, you can use the information you gather from the office to make determinations, using your knowledge and experience gathered from all possible sources I have discussed above, to create a proper proposal for this operation. By creating that proposal, in writing, you are covering your butt. Your employer or client is also covering theirs. You are unofficially agreeing (sort of), that this is the work you are doing. Even an invoice for equipment and other stuff if you are a contractor and a single piece of paper agreed to and signed by both parties will be enough to make everyone feel better that you know what you are doing. It will also make the employer/client feel that they are mitigating risk.
Is this too much? If you believe a legitimate, detailed proposal will be rejected, or misunderstood, then you will need to simply get moving and providing the components necessary to complete the project. You should also consider whether or not you have been placed under unreasonable time constraints for this project and whether or not you have enough independent control over the project. As an employee, you will have nearly no control of how you perform this work, and it will usually be mandated to you, in the simplest form possibly imaginable, for the most complex task. If you are a contractor, you can negotiate with the client and inform them of the necessities required to do this project, including a proposed timetable, your initial field assessment, your documentation of all the work you do.
Why should you document all the work you do while setting up a network? If the network goes down, guess what is going to happen? I don't even need to write it. This is a liability matter. To you, this may be a small network. To the business owners, it is their lifeblood. It is everything. Their server may house accounting records - or who knows what. Every business provides a different service or product, and they are recording everything. You should too. You can go back and say, here is what I did today.
Should you create a timetable? You should have a time table for yourself for the project, and one for your employer or client. Note: I am err'ing on the side of caution, because I believe any mistake could cost you a major problem.
Should you assess your own capabilities? You will probably want to
be honest with the client/employer and tell them that you do not have all the pre-requisites to complete the project, even if that means you will lose the project. If you deem this is appropriate, you need to have a detailed explanation as to why you cannot complete the project.
The success of every project is based on mutual trust, respect, and excellent communication. If any of these three components break down, the entire project may become risky. Can the project be completed and what does this require? If you believe you strongly can complete the project, you should continue on course, using the information you have gained through research and experience, to set up the network. A limited amount of information provided results in limited information I can give you. A small network typically consists of a server with multiple hard drives in a RAID array, external storage for backup, a multi-port unmanaged Gigabit router with one high speed business Internet connection coming in, and Category 6 wiring to all computers on the network. Basic networking functionality can be tested before the server is fully functional by using the
OSI model. If you have absolutely no knowledge about the OSI model, it is time to find as much as you can, as quickly as possible, or abandon the project.
My final thoughts: A learning curve is different for everyone. Do not feel defeated if this all fails. You will learn much from the entire experience. Just make sure it is not at your expense or the expense of others! Some times it will be. Here is a tip: If you really are clueless about certain concepts, spend the extra time learning. If your employer is flexible, they will let you do this. If they are shrewd and unreasonable, then you are going to have to act the same way, and this is unfortunate, but sometimes that happens. I don't know if you've been working for the business for 20 minutes or 20 years. I also don't know if you're a IT contractor, working for one, or doing this work as an employee. What I can tell you is that in every instance, the project will fail if communication breaks down. If mis-communication takes place, it must be corrected, respectfully, and immediately. The key to a successful project in IT will involve trials and tribulations. If you feel completely lost or uncomfortable doing a project, let them know. It will eliminate long-term problems. If you are given time to acquire the knowledge you need, or do the job in small increments as you experiment or get things right, you will succeed on further projects. If this is an employer, specifically, that is looking for a long-term investment in you, then they must know that you require further research to complete the project due to [insert reason here]. You will find out just how flexible they are, and whether or nor they are seriously ready to deal with you as their IT person. This is the key as far as I am concerned. If I didn't have access to employers who were decent and reasonable, and willing to accept time constraints, I would not have had much success moving forward on additional projects. It got to the point where I could deconstruct an entire office in an hour and set up a brand new one in an hour. I have no interest in rushing about like that any more, but I am dedicated
Do not rush your work. They will expect you to rush it all the time, whether employer or client.
Remember that how you present yourself and how you are perceived by others is very important. Therefore, it is important to keep a professional repertoire with the individuals you are working with when building their network. They must understand the risks of failing backups, and there must be something in it for you to continue maintaining this network if that is their goal. You should not take responsibility for millions of dollars of information that may be produced and stored on server(s) without things being put in writing. This is my personal advice, because projects often times can have overruns, misunderstandings, or disasters. Every system breaks down over time, so once the server is online, it essentially becomes a time bomb. You must be understand all of this, and so must the employer.
They have to be on the same level as you. I don't believe they are from the way you wrote this. I hope this has honestly helped you.