How do you follow the "SRS"?
 

Haven't flown Jets yet obviously.
I understand the speed reference systems helps you maintain V2+10, and V2 in single engine?
How do you "follow" this SRS? (What indication is it)?
When do you follow it?

Just stare at the flight director and you'll look like you know what your doing!

I only know about the Airbus A300 but I think the later Airbuses are basically the same.

SRS (speed reference system) is a Flight Director mode (not Auto Pilot) used during take off, that gives pitch commands through the F/D pitch bar to maintain V2 +10 with all engines operating and V2 with one engine inoperative.

The V2 speed is derived from performance calculations and is set on the ASI with the speed selector. When the "Go" (TOGA) levers are triggered on the power levers at the start of the take off the Modes "N1" and "SRS" are engaged and this is followed until acceleration (3000ft. AGL) or A/P is engaged.

Hope this helps.

It's the pitch information the FD is giving you.

In this case the pitch command is linked to speed(vs. altitude while in 'ALT' mode or glide slope when in 'GS' mode)