The ability to play Blackjack and count cards at a live casino depends on staying under the radar of the casino personnel that are on the look out for counters. Some of the characteristics they look for are found in the list of counter profiles.
Counters are generally young men who are dressed very casually no matter what they are betting. When watched, the casino will notice that the counters scout out a game that is favorable to play. Counters seem to prefer starting their betting level at a small chip level no matter what the buy in for when they take a seat. Counters do not tip, drink, smoke or talk to other players. They stay well within their focused bubble at the table.
The ways to avoid discovery is do not do any of the above and do the following. Play from $5 to $40 dollars at a time after buying in for $40 to $80. Play in a thoughtful manner, but not with a real air of confidence that you will win. Play in short sessions at odd hours and at different casinos. This will help to keep the staff of any casino from becoming suspicious. High stakes players are always noticed in any casino. The secret to playing unnoticed is to not try to make a killing at a single casino, but move the play around from casino to casino. Only play one shift a day and not lap to another shift. Refer to the chips in dollar amounts and not as colors. Never help another player play their hand as this may give away that you know a lot about playing Blackjack. Be sure to bet on time and bet the amount you want to play and do not hesitate on the bet.
If you are thinking of leaving a table, leave after a losing hand. Players rarely leave on a winning hand. Take insurance every now an then like you are playing a hunch and not a pattern of betting. Do not move away from basic strategy as a cover. Dealers do not normally know if you are playing smartly or not.
Wearing different outfits for various sessions can be effective as long as they are not outrageous and make you stank out from the norm of other players. Hats or jackets are a good way to slightly change your appearance. The use of real disguises is okay if they look real but not if they are easily detected. Things like fake beards and such may work if the look real on the player.