A Restoration Shaman's rotation is a budget. 
Riptide runs on its own 6-second clock, and every other cast is a choice between 
Healing Wave (Rank 10), which heals the most per second, and a cheaper heal that stretches the bar. Your mana against the time left makes that choice.
Before the pull
The one-minute builds cast nothing before the pull and keep no Water Shield. You start on a full bar.
Spending the bar
The simulated shaman decides each cast with one comparison: mana left, as a share of your bar, against fight left, as a share of the fight. Ahead, it casts the heal with the most healing per second. Behind, it casts the one with the most healing per point of mana. That keeps the bar emptying at the pace of the fight.
For a shaman the big heal is Healing Wave rank 10 at 2.5 seconds after Improved Healing Wave. A low rank of the same spell is the cheap one: it takes the same cast time, all your Healing Wave talents and your full healing power.
Priority
The list isn't a sequence. Whenever you can act, the highest line that is ready and whose condition holds is your cast. Beside each line are its casts a minute and the healing the build loses without it.
- 1Use the other cooldowns as they come up+478 HPS · 33.1 %
- 2Cast
Nature's Swiftness1.0/min+65 HPS · 4.5 % - 3Cast Riptide (Rank 3) if Riptide (Rank 3) not ticking4.0/min+51 HPS · 3.5 %
- 4Cast Healing Wave (Rank 10) if mana % > time remaining %19/min+119 HPS · 8.2 %
- 5Cast Healing Wave (Rank 9)3.0/min+113 HPS · 7.8 %
- Cooldowns first, once their mana won't overflow. Potions, runes, trinkets, Mana Tide and Blood Fury (Orc) are one line in the widget, so their worth is one number.
- Nature's Swiftness whenever it's ready. One instant heal at the pull, worth 4.5 %.
- Riptide when it has dropped off you. It is up 94.2 % of the fight and worth 3.5 %.
- Healing Wave (Rank 10) while your mana is ahead of the clock. On one minute that is nearly every cast: 77.0 % of your healing.
- Healing Wave (Rank 9) otherwise. It costs almost as much as rank 10. It only appears in the opening casts, after the first Riptide has put your mana a step behind the clock. It is worth 7.8 %.
Healing a party
A second and third boss make no difference to you: in our fights no one is hit, and the people you heal don't change.
The party build, under the switch at the top, is the one for five people. On one minute it spreads Riptide over all five and sends rank 10 Healing Wave round the party.
Cooldowns
Mana Tide Totem gives your party 290 mana every 3 seconds for 12 seconds. The simulated shaman drops it 40 seconds in, or half way through a shorter fight, once there is room in everyone's bar. It is a water totem, so it replaces your own Mana Spring Totem while it stands.- Nature's Swiftness makes your next heal instant. Our simulated shaman presses it at the pull and spends it on the first heal after Riptide, which the mana rule makes the cheap one. Save it for a rank 10 Healing Wave.
Major Mana Potion and 
Demonic Rune keep separate two-minute cooldowns, so take both. The simulator uses each as soon as its whole gain fits in your bar.- Trinkets. Our shaman uses
Talisman of Ascendance at the pull and again each minute. Its stacks come from the heals you land after it, so line it up with a run of Healing Waves. 
Serenity Field is 72 Spirit for 15 seconds, every 90 seconds.
| Cooldown | Uses | At |
|---|---|---|
 Blood Fury | 1 | 0:00 |
| Talisman of Ascendance | 2 | 0:00, 1:00 |
| Nature's Swiftness | 1 | 0:00 |
| Demonic Rune | 1 | 0:08 |
| Major Mana Potion | 1 | 0:16 |
| Serenity Field | 1 | 0:22 |
| Mana Tide | 1 | 0:32 |
What your log should show
Compare casts, not healing, with your Warcraft Logs report. In our fights every heal lands in full on a target at full health, so a real log's healing done will be lower while its cast counts should be close.
| Ability | Casts per minute | Of healing | Crit |
|---|---|---|---|
| Healing Wave (Rank 10) | 19.0 | 77.0 % | 23.0 % |
| Healing Wave (Rank 9) | 3.0 | 11.5 % | 23.0 % |
| Riptide (Rank 3) | 4.0 | 11.5 % | 4.2 % |
| Nature's Swiftness | 1.0 | – | – |
| Blood Fury | 1.0 | – | – |
| Major Mana Potion | 1.0 | – | – |
| Serenity Field | 1.0 | – | – |
| Talisman of Ascendance | 2.0 | – | – |
| Demonic Rune | 1.0 | – | – |
On a one-minute single-boss fight, rank 10 Healing Wave should be about 19.0 casts a minute, with Riptide each time it drops off.
Healing Wave rank 10 crits 23.0 % of the time here: your sheet's spell crit plus Thundering Strikes' and Tidal Mastery's 10 %. Riptide's crit reads far lower, because the table counts its ticks as hits and our model never lets them crit. Since Blizzard's 24 September notes, Riptide can crit in game, so expect a higher number in your own log.
Uptimes
| Buff or debuff | Uptime | Times per fight |
|---|---|---|
| Riptide (Rank 3) | 94.2 % | 4.0 |
| Ascendance | 33.3 % | 2.0 |
| Ascendance | 33.3 % | 2.0 |
| Blood Fury | 25.0 % | 1.0 |
| Serenity Field | 25.0 % | 1.0 |
| Mana Tide | 21.7 % | 1.0 |
| Nature's Swiftness | 2.5 % | 1.0 |
Aim for Riptide on your main target about 94.2 % of the fight.