Use a sequence in the RH to mirror the sequence in the bass at bb.2-4. In bb.4-5 the bass falls a third, so keep to the nearest available position in the RH. In 5-7 the rising fourth followed by a step should have contrary motion in the RH. The bass octave ar b.7 requires no change or repetition in the RH chord.
But the main advantage is in fact one of the reasons why the system of bass figuring was originally devised - it allows flexibility in the choice of accompanying instrument, and the same part can be used for organ, harpsichord, lute, or theorbo, each of which has its own accompanying style.
The texture and tessitura of the accompaniment can also be adusted to suit the instrument accompanied.
In the many baroque sonatas which allow alternative instrumentaion the accompaniment will not be the same for the quiet flute or recorder as it is for the more extrovert oboe or violin.
On a more mundane level, it is in fact easier to accompany from figures (when the facility has been acquired), since the player can adapt the accompaniment to his own hand and technique.
What is required is often a great deal simpler than that which many written-out accompaniments provide.
(from INTRODUCTION of CONTINUO PLAYING according to Handel)
1. Play one note in the left hand (LH) and and three in the right (RH). The RH notes are the octave, fifth, third above the bass.
2. Move to the nearest available position of the next chord. The essence of fluency in figured bass playing is that you should be equally familiar with all the possible RH shapes of each chord. Thus the first chord has three possible shapes, depending on whether the octave, third, or fifth is on top. The shape you use for the succeeding RH chord will depend on your point of departure. You will notice that different bass intervals require different number of notes to be changed in the RH. If the bass moves a third, only one RH note will need to be changed. If you are playing these exercises on an organ, you should tie any common notes between chords.
3. When the bass moves by step, the RH parts must move in contrary motion to it. This avoids the parallel fifth and octaves which would result from similar motion between upper patrts and bass, and is the main exception to the principle of moving to the nearest available position of the next chord. Seventeenth- and eighteenth-century tutors are strict about parallels, and they should certainly be avoided in basic exercises.