All your movements, gestures, and postures in the chancel and the sanctuary need to serve the purposes of the liturgy—clearly, deliberately, and gracefully. There should be nothing slovenly, casual, or idiosyncratic in anything you do while serving at the altar. Pay attention to the other servers, heed the directions that come from the celebrant, deacon, acolyte, or MC, and cultivate the utmost responsiveness and attentiveness.
Ceremonial actions and ritual gestures should be performed at a stately pace, neither too slow nor too quick, but with confident, composed ease. Move with solemn dignity, even when things go wrong or you find yourself out of place or taken by surprise. Graceful movements and quiet assurance can cover for a multitude of errors.
Take care always to make the appropriate reverences in coordination with the other servers and the altar party, bowing, genuflecting, striking the breast, and signing the cross at the proper moments.
Always keep your eyes focused ahead, paying attention to relevant liturgical action. Always be aware of what is going on in the liturgy and anticipate what is going to happen next and what you may have to do to help out. Do not let your gaze wander aimlessly, and never stare into the congregation. Do not fidget, and do not play with your hands or nails. Unless carrying a liturgical implement or performing a particular action, always keep your hands folded at your breast, palm-to-palm, upward, with your right thumb crossed over the left. Whenever you are carrying something or doing something with one hand, always place the other hand flat on your breast.
Walking
Hold yourself straight with your shoulders back and your head erect. Face directly the point to which you are headed. When walking in procession, try not to sway from side to side. In procession, you should walk slowly but at the appropriate pace to maintain the procession’s formation clearly and tightly. Maintain a suitable distance from those ahead of you and those behind you. Sometimes you will have to walk more briskly, sometimes more slowly, but always modulate your pace inconspicuously, so that your movement never seems jerky or impulsive. When walking side-by-side, take special care to maintain symmetry and to move in tandem with the server next to you, making the appropriate reverences at the same time.
Turning
Corners should be turned squarely, without making it obvious in a military fashion. In general, you should move in the chancel and sanctuary at right angles and straight lines, turning corners crisply but gracefully. Try to avoid walking diagonally or in a zig-zag fashion. Take particular care that your movements in sanctuary and on the altar steps are undertaken with the utmost reverence for the Blessed Sacrament in the tabernacle. Try to avoid walking backward, but do not unnecessarily turn your back to the Sacred Species exposed on the altar. Take one step backward, if necessary (in taking and holding the missal stand, for instance), but otherwise attempt to pivot gracefully and to proceed on your purpose gracefully and efficiently.
Sitting
When seated, put your feet flat on the floor, sit up straight, and keep your hands on your knees. Never, ever, sit with crossed legs or knees. Put your hands on your knees so that the tip of your middle finger on each hand is at the top or bottom of your kneecap or somewhere between. Do not fidget and do not amuse yourself by idly letting your eyes wander around. During the readings and the sermon you should look straight in front of you and pay attention to the words. When the entire altar party or more than one server go to sit in the chancel, always sit down together, at the same time, and likewise rise in tandem, as prompted. Always pay attention to the celebrant, deacon, acolyte, or MC for such cues.