I think you would get better answers if you question was more specific. ie: Stream fishing, lake, river, ocean; type of fish and gear you are using....lures, bait; type of fish....etc.

 

Reasonable suggestion. Here I’m talking streams with current.

 

Fishing with bait (worms) in a stream I use a 3/16"diameter (or 1/4") X 1 to 2" long piece of black surgical tub which I slip on the line before adding a swivel, leader, and hook. Most of the time I tie the hook directly to the 4 to 8# main line, no leader. If you are having trouble with line twisting then add a swivel and use a leader. Then I position the tube any where from 12 to 24" above the hook and slip a piece of what is called Bullet weight (3/16" lead coil), cut to a length needed depending on the speed of the water; 1/2" to 2". The lead is slipped about half way into the tubing from the hook end and that combination can be slid along the line into what ever position you want above the hook and also can be easily repositioned. The reason it goes half way in from the bottom is that the top of the tube remains flexible and can "bounce" off of obstacles in the water reducing the number of hang up.
If you are using night crawlers I recommend using a worm threader and only use 1/2 of a large worm. Insert the threader about 3/8" from the pointy end of the half worm and push it up through the center so that the worm is fully threaded on the tube. Insert the hook point in the hollow end of the tube and keeping the leader pulled tight to keep the point in the tube slide the worm off on to the hook so it is fully on the hook & line and as straight as possible....which means it will go up the leader a ways.
I guarantee if the fish are hungry this will catch more fish than any other way I know.

A hint on fishing this set up:
On a stream I suggest that facing the stream (from shore) with up stream being 9 AM and down stream 3PM make you cast across the stream at about 11 AM, let the bait or lure follow the current down to 2 PM keeping the line tight by reeling in as needed so it doesn't catch on the bottom. At about the 2 PM position start reeling the line back in, 6 out of 10 times as the bait changes direction and speed is where you will get a bite. If the fish misses immediately drop the tip of your rod back so the bait stays in the same area and the fish often will come back and try again.

 

Fishing with bait (worms) in a stream I use a 3/16"diameter (or 1/4") X 1 to 2" long piece of black surgical tub which I slip on the line before adding a swivel, leader, and hook. Most of the time I tie the hook directly to the 4 to 8# main line, no leader. If you are having trouble with line twisting then add a swivel and use a leader. Then I position the tube any where from 12 to 24" above the hook and slip a piece of what is called Bullet weight (3/16" lead coil), cut to a length needed depending on the speed of the water; 1/2" to 2". The lead is slipped about half way into the tubing from the hook end and that combination can be slid along the line into what ever position you want above the hook and also can be easily repositioned. The reason it goes half way in from the bottom is that the top of the tube remains flexible and can "bounce" off of obstacles in the water reducing the number of hang up.
If you are using night crawlers I recommend using a worm threader and only use 1/2 of a large worm. Insert the threader about 3/8" from the pointy end of the half worm and push it up through the center so that the worm is fully threaded on the tube. Insert the hook point in the hollow end of the tube and keeping the leader pulled tight to keep the point in the tube slide the worm off on to the hook so it is fully on the hook & line and as straight as possible....which means it will go up the leader a ways.
I guarantee if the fish are hungry this will catch more fish than any other way I know.

A hint on fishing this set up:
On a stream I suggest that facing the stream (from shore) with up stream being 9 AM and down stream 3PM make you cast across the stream at about 11 AM, let the bait or lure follow the current down to 2 PM keeping the line tight by reeling in as needed so it doesn't catch on the bottom. At about the 2 PM position start reeling the line back in, 6 out of 10 times as the bait changes direction and speed is where you will get a bite. If the fish misses immediately drop the tip of your rod back so the bait stays in the same area and the fish often will come back and try again.

Confused with the 24 hr clock. Also not understanding if the current is flowing left or right?

 

For trout in streams, I use a casting bubble with a 2-3' leader, to a spoon, bait, or fly depending. Depending on what's on the business end, I'll add a split shot or two. Deeper rivers I've used small slip bobbers or just drift fished my bait like I would for steelhead.

 

There are 24 hours in a day but most clocks and watches with dials only display 12 with 12 at the top, 9 on the left and 3 on the right. I obviously did not make it clear enough for everyone.
Standing at the stream edge with upstream on you left and down stream on the right. Being on the other side of the stream would be the opposite. A little interpolation of the fact that the bait will obviously be going from 11 AM to 2 PM means from upstream to down stream or left to right could have cleared that up.

 

General rule of thumb is clearer water = longer leader.

 

Fishing a Texas rig will have the weight pegged next to the hook.

OP didn't provide enough variables in the question. Like....what are we fishing for?