"It's madness. Every time it comes around, it shortens your life by another two years. You would never conduct any other business in the same manner."

If only it was as easy as creaking up your laptop lid, opening your Football Manager 'save' and giving the mouse a few clicks.

However, the harsh reality is, it is just a tad more complicated than that. But just how does it actually work?

With the January window open, we dusted off our BBC Scotland detective hats and made a few calls to find out what goes on behind closed doors.

Drawing up a shortlist

So you are in the shoes of a club manager and have identified a problem area in your team. You need a clinical goalscorer, or perhaps an imposing centre-back. So what next?

You will firstly have to liaise with your scouting and recruitment department, providing your club has one.

"You're in constant dialogue with the manager," a former top-flight director of football tells BBC Scotland. "You need to know what type of player they're looking for. This takes place on an ongoing, weekly basis.

"You will often be instructing your scouts to look at certain types of players a year in advance. Say you need a left winger, do you need one that goes on the outside, one that'll cut inside or one that'll score at the back post?"

Once the specifics have been ironed out, your scouting team will aim to provide you with a longlist of suitable targets.

Then you are treated to endless hours of going through all potential options, narrowing the list down to your top four or five targets you can pursue in the upcoming window.

Tapping up & private investigators

The longlist has been cut, you have your chosen few. The easy bit is done, now it gets more difficult.

The official way of making the next step would be to have a verbal discussion with the potential selling club before an official bid is lodged.

The buying team must have consent from the selling club before discussions begin with a player, unless they have fewer than six months remaining on their deal.

However, you may be familiar with the term "tapping up". This is a prohibited process which involves a representative from the buying club approaching the agent or player without speaking to the selling outfit first.

"It happens," an ex-Premiership manager says. "With all the work you do, all you really want to establish is if the player will come to your club. A lot of work would have to go on for you to find out at the very end the player isn't interested.

"A lot of times, everything is done by the book. But when you start to look outside Scotland, knowing whether the player will come or not is something you need to find out."

Tapping up is not the only questionable unofficial method that goes on in football transfers.

While endless amounts of video content is available on scouting systems at the click of the button to find out every detail about a potential target's playing ability, finding out their personality off it is more tricky.

When millions of pounds are involved in transfer fees and contracts, clubs want to know if they are going to be blowing that on someone who is going to cause disharmony in the dressing room.

Character references are a usual route to finding out that information from a player's ex-colleagues, but one source tells BBC Scotland that they are aware of private detectives being used south of the border.

"You get the same characters in every dressing room," they say. "If you're getting up to offering people £40,000 a week, it might be worth hiring one to check if the player likes a drink or is at a casino until the early hours."

Annual leave entitlement & £1,000 cash in £1 notes

Don't worry, for the purposes of this, we are not asking you to tap anyone up or hire a private detective.

Let's say the selling club have given you permission to speak to the player after encouraging initial talks and a successful bid.

The next step is discussing personal terms with the player. Enter the agent. Now agents don't have the best reputation in the world of football, but is the stigma unfair?

"We are easy targets for clubs and fans," one tells BBC Scotland. "We get the blame for everything. It's just the nature of it. We're just there to help the player and give them options."

So what exactly do they assist their clients with? Agents are on hand to get their player the best contract possible.

A lot of that comes down to wages, but they also have a responsibility to make sure the club is financially secure so their client can get paid and get paid on time.

If those boxes are ticked, they will also try to establish where the player will fit into the manager's plans, what the signing-on fee will be, what the bonuses are and how long the contract is.

One you probably haven't thought of is annual leave entitlement. Of course, there is only one time in the year this can realistically be used and that is between the end of one season and the start of the next.

While agents are regularly given a bad rap, one former Scotland international highlights their importance by recalling a signing experience without one.

"I remember signing for a club and getting a £1,000 signing-on fee in £1 notes," they say. "There are a lot of good agents out there. Some can be pretty poor and awful, but they're not villains at all."

Two-day medicals & TMS paperwork

Both the transfer fee and personal terms are accepted. Job done, right? Think again. The signing player will then be expected to take a medical.

When a multi-million pound deal is at stake, these can sometimes be done over two days, prompting a nervous wait for everyone involved, whereas clubs with fewer resources will have to rely on their medical department picking something up.

Hitches are rare, but not impossible to come by. David Turnbull's move from Motherwell to Celtic occurred a year later than planned because of a medical issue, while Parkhead favourite John Hartson famously failed a procedure at Rangers before signing for their city rivals.

Medicals aren't the only cause for concern, though. Deals being processed on deadline day can collapse because of paperwork issues. Then you've got the visa issues brought about by Brexit.

Any non-British player needs to be assessed on a Home Office system where points are awarded for things such as international appearances, how successful their existing club is, and how much they will be paid.

The majority of those coming here won't hit the threshold for a permit to be granted automatically, so a case for a Governing Body Exemption has to be put to a six-strong panel. It's a time consuming process involving a forest-full of paperwork.

And after all that, the relevant documentation must be uploaded to the Transfer Management System (TMS) by the scheduled deadline. If that process has begun before, you receive an extra hour to get the deal done.

Permitting all that goes smoothly, it is then about your club's liaison officer assisting with finding accommodation for a player, or even a school for their children to attend, while your new signing hoists the club scarf above their head for media purposes.

Good work everyone. We can relax now, surely? Not according to this former top-flight boss...

"You should be made to wait a year before you start congratulating each other, just to see how they do," they add.