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All players at the table are responsible for ensuring that each winning hand is scored correctly and to the maximum points.
First find the number of fan (doubles): Add the number of fan given by the yaku (at least one), the number of dora tiles, kan dora tiles and, in case of a riichi hand, the number of ura dora in the hand. This sum is the fan value of the hand.
Then the base value of the hand, the minipoints, is calculated. Round the number up to the next 10. (e.g. 32 minipoints are rounded up to 40). In case of a seven pairs hand, the hand is worth 25 minipoints and there is no rounding up. For hands with five or more fan the minipoints are irrelevant.
The value of the hand can now be found in the tables on A-1. The tables are further described in 4.1.3. To the value in the table are added 100 for each counter on the table in case of self-draw, and 300 in case of winning on a discard. In addition any riichi bets from players who didn’t win the hand are collected by the winner.
In case more than one player wins at the same time, the discarder settles the score with each winner individually. Each winner receives the value of the hand including the value of counters in play.
In case more than one player wins at the same time, the riichi bets from players who declared riichi without winning go to the winner closest to the discarder’s right. Riichi declarers that win, always get their riichi bet back.
When scoring is done with sticks, players should put the sticks on the table where all players can see them during the exchange. When scoring is done with sticks, players are obliged to count up their sticks when asked to by opponents. The game continues if a player’s score goes below zero; the player borrows score sticks from an opponent or the referee.

You always get minipoints for one the three following ways of winning:

Minipoints for winning:
Concealed on a discard	30
Seven pairs (no further minipoints are added)	25
Otherwise (Self-draw or Open hand)	20

Add minipoints for pungs and kongs in the hand. Chows have no minipoint value. If the winning tile finishes a pung, it counts as a concealed pung in case of self-draw, and it counts as an open pung in case of winning on a discard.

Minipoints	Open	Concealed
Pung, 2-8	2	4
Pung, terminals/honours	4	8
Kong, 2-8	8	16
Kong, terminals/honours	16	32

In addition 2 minipoints are added for each of the following:

2 minipoints for:

Pair of dragons

Pair of seat wind

Pair of prevailing wind

Winning on an edge, closed or pair wait

Winning on self-draw (except in case of pinfu)

Open pinfu

The 2 minipoints for edge, closed or single wait can be claimed even if the hand is waiting for other tiles. Edge wait is 1-2 waiting for 3 or 8-9 waiting for 7. Closed wait is waiting for the centre tile of a chow. Single wait is waiting to finish the pair.
Edge wait: winning on
Closed wait: winning on

The highest-scoring possibility decides which set is finished by the winning tile. Consider the following waiting pattern:
waiting on or
Winning on the 7, the tile can either finish an edge wait (claiming two minipoints) or finish the two-sided 5-6-7 chow, claiming no minipoints, but instead a yaku for pinfu on a concealed hand. The highest-scoring possibility must always be chosen.

In special cases like
  even though it is only possible to win on
no minipoints can be claimed, since the tile finished neither an edge wait, a closed wait or a single wait (pair wait).

2 minipoints are awarded for winning on a self-drawn tile. This is voided, however, in case a yaku is claimed for pinfu.
Open pinfu is an open hand worth no minipoints (except the 20 minipoints for winning). It is rewarded 2 minipoints. E.g.:
    

Instead of calculating manually the value of the hand, the tables provided are recommended. For completeness, however, the calculation procedure is given here. For hands worth five or more fan, the table for limit hands is used. For hands worth less than five fan, the value is calculated thus:
The base value of the hand (the minipoints rounded up) are doubled by the number of fan plus 2. This figure is the base figure to be paid by all three opponents in case of selfdraw. For East, however, the figure is doubled one more time. East receives double payment, but also pays twice the amount of the base figure in case of an opponent’s self-draw. Payments are rounded up to the next 100, though never exceeding the value of a mangan.
In case of winning on a discard, the discarding player must pay for all opponents, incl. East, i.e. four times the base figure if the winner is not East, and three times the doubled base figure if the winner is East. The payment is rounded up to the next 100, though never exceeding the value of a mangan.
In addition to this is the value of counters and riichi bets on the table.

The scoring tables are categorized by whether the winner is East or not, and whether the win was on a discard (ron) or on self-draw (tsumo).
In the relevant table, use the column that gives the fan value of the hand and the row that gives the minipoint value of the hand.
The table East on self-draw (Tsumo) gives the amount that each opponent should pay to East. The table Others on self-draw (Tsumo) gives two numbers; the largest number is the payment from East, the other number is the payment from each of the two other opponents. The tables for winning on a discard (Ron) gives the amount that the discarder should pay to the winner. The tables for limit hands gives the amount that each opponent should pay to a self-drawn win. In case of winning on a discard, the discarder pays for all, e.g. for a haneman the payment is 18 000 to East or 12 000 otherwise.
The value of any counters and riichi bets are added to the value found in the tables.