here’s a pretty good method:
use a longer leader than usual. tie the leader into a loop using a double or triple surgeons. determine how long you want the dropper to be and clip the loop at that length from the surgeon’s knot.
Here is a quote from Ken Abram’s home page;
“There is a method for fishing in tidal rivers that will teach you more in a short space of time than any other method. It is the use of droppers. You will learn more about fly selection through using droppers for one year than you can learn in any other way.”
I’ve been using droppers regularly for a few years now. Not only in tidal flow but in the surf too. Early season last year, when there was a lot of small fish around, catching two dinks at a time was a good way to put a bend in the rod.
Sometimes you even catch a couple that aren’t so small 
Which begs the question “How do you rig your droppers?”
I’m in the habit of tying a clinch knot off the bend of the hook.
Jay Mirakoshi, on the west coast, uses a very small metal ring to attatch the leader and two tippet of varying length to. At least for surf application.
I like leaving a long tag on a bloodknot, but cannot say that this is effecient.
…lee s.
What I do is when I prepare my tippet for the loop2loop connection I leave an extra long tag end.
In other words, I take 3’ of tippet and tie a double surgeon’s loop one foot into it, so one tag is two feet, the other is one foot long.
(I don’t really make them that long but you get the idea.)
“such a day, Rum all out.
Our Company somewhat sober.
A damn’d Confusion amongst us!
Rouges a plotting; great Talk of Separation,
So I look’d sharp for a prize; such a Day took one
with a great deal of Liquor on board,
so kept the Company hot,
then all Things were well again.”
Blackbeard’s Log
[This message has been edited by dudley (edited 23 March 2006).]
Somewhere way back in the day I posted instructions on this. Can’t seem to find it. I do recall it was in a response to a call from Dave to post tips.
It may have been archived.
LF - do you have a post from me that I think was titled Tip - Droppers?