First, go to a park and put the braided line on very tight. Tie it to a post and then walk with rod and reel to empty spool. At bottom of spool, re engage spool and reel hard without moving to get tension on line. Slowly walk toward end of line to manage line tension. This really only has to be done the first time but will help with line digging in.
You don't have to cast easy with it, but it will take some time for you to get comfortable with throwing it hard and getting the distance. With that said, if you don't have the reel brakes and spool tension knob set correctly then you will get a backlash much more often.
Proper settings for casting reel
Spool tension knob (by reel handle, puts more or less tension on the spool; is used centering spool as well as putting base amount of friction on spool shaft at friction plate under knob).
1. tighten spool tension knob until line will not run out when reel is disengaged (thumb on reel, tighten knob a turn or two until just snug). With reel disengaged, you should be able to at this point take your thumb off the reel and spool will not free spool with the weight of lure you are casting. SLOWLY loosen spool tension knob until lure just barely begins to pull line out by its own weight.
Brake settings (various reels are different some are centrifugal, some magnetic, some both, and some like the new Lews Team Lite and BB2 Pro are a new breed of centrifugal allowing fine (infinite) adjustment of brakes (ie. not just 1 or 2 but infinite choice of how much or little braking power.
2. If you have a centrifugal brake set up, set / engage 2 brakes and close reel side plate.
2a. If you use a magnetic brake then set it to 6-7 on the side dial...maybe even 8 to start with.
2b If reel has both, set only the centrifugal brake initially.
2c. If new Lews mentioned above then set external brake setting for 5-6.
3. Now this setting is just the starting point. Make a cast, you shouldn't backlash at all, but distance will be minimal. Slowly reduce settings to loosen up reel.
3. if centrifugal brakes, slightly reduce the spool tension knob to get increased distance. At some point after a good bit of practice you'll reduce your brake setting to only 1 brake.
3a. Slowly reduce magnetic brake settings until you increase distance and only get slight overrun. Same for new Lews systems.
3b. If you have a reel with both slowly reduce the brake power but increase the mag to fine adjust your braking on the reel.
Feathering spool edge during cast.
4. As you cast, learn to practice putting your thumb on the edge of the spool to 'feather' the speed of the spool. This will take practice but in the end you'll be able to control your line on the spool with just the slight resistance on the spool with your thumb. You'll never only use your thumb but you can eventually open the settings up slightly more and feather the reel to get the most distance. With the new Lews system the new brakes are basically doing this for you.
Reel turn during cast
5. Some will turn a reel during the cast so the spool becomes vertical during the cast. For some reason this allows line to more smoothly exit the reel even if there is a slight over run. This will also take practice.
The basic idea to get used to casting braid with less backlash is start with tighter settings and slowly loosing them up. Following this list to adjust reel, you can also more quickly learn to cast harder which will get you more distance and allow you to also cast into the wind.
Take your time. Additionally, all of the above can be used with mono line to increase distance and reduce backlash.
Hope this helps you guys increase your cast distance and get more out of your casting reels.