Don't be scared. Just because Slabhead himself is struggling to understand the Uefa Nations League, it doesn't mean you will. It's not (quite) as complicated as you might have been led to believe.

1. What is the Uefa Nations League?
An attempt to make international football more competitive with more high-profile games that have something at stake.

All of the European countries are separated into leagues based on their Uefa coefficient, so in theory, we should see more evenly matched contests than qualification campaigns tend to bring.

There will be promotion and relegation between the leagues, and they also serve as a potential route for qualification for Euro 2020 (we'll get onto that later).

2. How does the Uefa Nations League work?
The 12 highest-ranking nations (according to Uefa's coefficient system) are in League A. The next 12 are in League B. The next 15 are in League C. The 16 lowest-ranked nations are in League D.

Each League (A, B, C ,D) is split into four groups. There is promotion and relegation between each League.

The draw for the Uefa Nations League 2018-2019 groups took place in January. This is how League A, B, C, and D shapes up:

Between September and November this year, each team will play each other twice - home and away - in the usual round robin format. So, England face Spain and Croatia twice each in the next few months.

The four winners of each group in League A will then progress to the Uefa Nations League finals, to be played in June 2019 in one of the four

nations that make the finals. This will consist of two semi-finals, a third-place play-off and a final. The winners will receive this trophy:

The team that finishes bottom of each group in League A will be relegated to League B for the 2020-2021 edition.

The first-placed team in each group in Leagues B, C and D will gain promotion to the League above.

The team that finishes bottom of each group will be relegated (except in League C where the three four-placed teams and the worst third-placed team are relegated). There is no relegation from League D.

That's about it... until you get on to Euro 2020 qualifying.

3. What about Euro 2020 qualifying?
First things first: the Euro 2020 qualifying format remains (almost) unchanged. 

Teams will be drawn into 10 five- or six-team groups that are independent of the Uefa Nations League. These will look very much the same as they have in years gone by. So the Uefa Nations League does not spell the end of Germany beating San Marino 7-0 at home and 8-0 away, as they did in World Cup 2018 qualifying.

This time qualifying games will be played over a shorter period of time: between March and November 2019.

The top two teams in each of the 10 groups will qualify for Euro 2020. That accounts for 20 of the 24 teams at the next Euros (there's no host nation this time), so what about the final four?

This is where the Uefa Nations League comes back in

4. How does the Uefa Nations League play into Euro 2020 qualifying?
This is a little complicated, but bear with us.

There is no play-off place for the teams that come third in their Euro 2020 qualifying groups (as used to be the case). Instead, play-off positions are decided by Uefa Nations League performance.

There are 16 play-offs places to be filled. Each League (A, B, C and D) within the Uefa Nations League will get four play-off places.

These are given out to the teams that finish highest in each Uefa Nations League group but also did not qualify for Euro 2020 through the traditional means.

So, for example, if England win Nations League A Group 4, but fail to finish in the top two places in their Euro 2020 qualifying group, they are given a second chance to qualify: through the play-offs.

If there are not four teams within a given League that have already failed to qualify, the remaining spots go to the League below. 

Four sets of play-off semi-finals and finals are then played (in March 2020), with the winners of each final making up the final four places at Euro 2020.

So four teams from League D will contest semi-finals and a final, and one of Azerbaijan, Macedonia, Belarus, Georgia, Armenia, Latvia, the Faroe Islands, Luxembourg, Kazakhstan, Moldova, Liechtenstein, Malta, Andorra, Kosovo, San Marino or Gibraltar will qualify for Euro 2020.

Whether or not that is a positive - or indeed whether teams might start losing games in order to fall down the rankings and into a lower League so that they have an easier play-off path to future tournaments - is a debate for another day.

Simple, isn't it?