A FIOS installation typically consists of installing a buried cable connection into your house. Your provider will schedule an installation with a Buried Service Wire Group (BSW). They will initiate a request with your local utilities to locate and mark any existing buried utility connections (telephones, gas, water, electricity, etc). In many states they can't start the digging process until this task has been completed. They will also mark where they will be running the cable and mark the location for the connection box. You should make them aware of any sprinkler or other underground pipes you may have installed, that are not part of any utility company's responsibility.
Once all of this is done your BSW tem will schedule an installation date. Installation will vary from location to location and vary considerably from job to job. In most cases they will have to make cut in your lawn to install the FIOS cable. Generally speaking most teams will put some seed back over the dead trench, but remember they are technicians not landscapers, so you may want to re-apply seed and fertilizer once they have finished. The cable installed will be connected to box but will be exposed at both the entrance and terminus of the line. There may be some extra cable coiled and exposed on the ground. Try to keep the cable as neat as possible to prevent people injuring themselves, and to keep the cable from becoming damaged.
Next a representative from your service provider will connect the cable to the system and check the line to make sure everything is working properly and there are no errors. Once this is completed the line will be run throughout your home or office. Once the lines are run and connected your service provider will need to 'turn on' your service. You should not stop or disconnect your existing service until your new service has been up and working for a few days.