Arms are the smallest of the show muscles and the easiest to overtrain. Because pressing and pulling already work your triceps and biceps, a little direct work goes a long way. The formula: a few hard sets, strict form, steady progression.
Give arms a small, fixed slot
Two to four direct sets for biceps and the same for triceps, at the end of two workouts a week, is enough to grow. Remember the indirect work: every row and pull hits the biceps, and every press hits the triceps, so ten to sixteen hard sets a week across everything is plenty.
More is not better. If your elbows ache or your pressing stalls, cut direct arm volume in half before you add anything. Put the slot in the calendar as part of those workouts, not as an optional extra for whenever the session ran long.
Curl with control
Stand tall with a dumbbell in each hand and your elbows pinned to your ribs. Curl by bending the elbow only: no swinging the torso, no shrugging. Take two seconds to lower every rep, because the lowering half builds as much as the lifting half.
If you cannot keep the elbow still, the weight is too heavy. Keep the wrists neutral and the grip firm; letting the wrist bend back turns a biceps exercise into a forearm complaint. A few partials at the end of a set are fine; swinging from the first rep is not.
Hit the triceps from two angles
The triceps has three heads, and the long head only fully stretches when the arm is overhead. Pair one overhead movement, like a dumbbell overhead extension, with one arms-down movement such as close-grip push-ups.
Reach a full lockout on every rep, but stop just short of snapping the elbow straight. Full range, controlled speed, no bouncing out of the bottom. Two sets of each, twice a week, is a complete triceps plan once pressing is already in your program.
Use intensity you can recover from
Isolation exercises handle failure well, so take the last set of each exercise to one rep short of failure — but only while the form stays strict. A "failure" reached by swinging is just junk volume.
Spread the work across the week. Two short arm finishes beat one fifteen-set biceps blitz that leaves your elbows aching for days.
Progress steadily and write it down
Add reps before weight. When you reach the top of your rep range on every set with clean form, move up by the smallest available jump next session.
Log every set in Bulky. Arms grow slowly, so the log is how you tell real progress from a good pump: four weeks of added reps is proof. Give any new weight two sessions before you judge it; arms respond to steady accumulation, not to single heroic sets.