[chrs]

Sure so as you did correctly the first person posts what speed and the time so either
min speed 4 secs
mid speed 2 secs or
max speed 1 sec
To following people can then add on top of this until they reached the max of five posts
e.g
- You started with mid speed 2 seconds
- the next person should then post something like: adding 4 secs
- the next: 6 secs
- then: 8 secs
- and finaly: 10 secs
Now the series is full as there were 5 posts and the next person who posts will start a
new series. Again either
min speed 4 secs
mid speed 2 secs or
max speed 1 sec

Once you completed a series of alll speeds, so once min, mid and max speed, you can post up to 6 times per series, so for max speed instead of:
4 secs, 8 secs, 12 secs, 16 secs, 20 secs; which totals 60 seconds
it would be:
4 secs, 8 secs, 12 secs, 16 secs, 20 secs, 24 secs; summing up to 84 secs.

The first series of each speed should look like this (posts seperated by semi-colon)
min speed:
4 secs; 8 secs; 12 secs; 16 secs; 20 secs
mid speed:
2 secs; 4 secs; 6 secs; 8 secs; 10 secs
max speed:
1 secs; 2 secs; 3 secs; 4 secs; 5 secs
hope this helps