I thought I'd add my 2 cents, as i recently took up fishing again, and had to pretty much re-learn technique from scratch. I used to fish as a teenager, in England. The fishing consisted off pier fishing, with 5ft-7ft rods with heavy duty tackle, and beach fishing, with 12ft-18ft rods. I always used baitcasters. What I've learned over the last 2-3 weeks: 1.Casting into the wind is very bad for nests ( brit for backlashes). To compensate, you have to release thumb late, and cast low. 2. Always have your thumb lightly touching the line on the reel. You can control nesting by applying more pressure when you feel the slack. You can also control distance very easily. 3. For a 7ft rod, use 2 - 4 ounce weights for large casts. For bigger rods, use 3-8 ounce(6-8 for heavy currents). When the weight is about to hit the water, apply thumb pressure, then release again to let it sink (big nests from not thumbing when you hit the drink;the reel is spinning, but the weight has just lost all momentum). 4. If you notice slack or line thats lifted off the reel, cast out, drop the tension on the brake, and pull out till its all smooth,tighten brake, and reel it in again tight. 5. WET YOUR THUMB BEFORE YOU CAST! otherwise your gonna burn your skin. 6. Theres nuances to thin and thick line, so wind the reel with average 20 - 40lb test. Hybrid casts very nice and smooth. 7. Multi-filament/Spyder is horrid stuff for untangleable nests.
Go practice on a beach or mowed field, with different sized pear shaped weights. Concentrate on the motion and timing, then start upping speed and distance. Once you have that down, try casting into the wind (for thumb control), and then start aiming for specific areas to increase accuracy. A few hours casting on a field, at brown patches or whatever, will do wonders in a short period of time.

Practice, practice and more practice. You will get the hang of it it in no time. Use different weights and DO NOT THROW AGAINST THE WIND.

mono is better bradded cost to much to learn with. and it took me a while to learn to master my baitaster, i used the cheap mono when i started out on my baitcaster,, keep your brakes tight and when you start to get better loosen up on the brakes

I USE BRAIDED LINE AND ONLY FISH WITH SHIMANO
REELS. BAITCASTERS ARE GREAT, BUT IF YOU WANT TO FISH WITHOUT THE BACKLASH,
JUST GO BUY A SPINNING REEL.

my personal preference in teaching someone to cast with a baitcaster has always been to put heavy test line on it on a nice stif MH rod. The heavier test seems to be easier on the baclashing issue. Im also a big fan of learning on penn X09(x=1-2). Ive taught many many people(including myself when i got back to heavy fishing a few years ago) how to cast with those little reels on a cheapo ugly stick(plus the rig cost sub 80$ and the reel lasts along time if taken care of and not tinkered with(my poor 309 is dead ))

Another mistake i see to many people making with larger reals in sw are over/under weighting and baiting. You can fudge the line weight in a rod a bit.....but that weight rating realy is were the rods going to cast better. Im guilty of it off places like umphreys pier when the currents raging, but i do it as little as possible. Ive helped out so many younger kids(im not exactly oan old fart but i have een at this a while....though i bow in the presence of many masters here) and mom-son groups on the pier theat either have 8 ounces plus a huge piece of bait on a bass-rod, or are trying to fish a MH 6' and a large zebco or baitcaster with a 1/2 ounce weight and a tiny hook. Funny how far a ittle kid can cast if you take five minutes to help them....