Pick a lakeside base first
Lake Bosomtwe is a different kind of outing from a day of museums and markets in Kumasi. Choose it when your group wants time by the water and a slower schedule. The most useful first decision is where you'll actually spend that time.
Select a host or venue with the facilities your group needs. A pin for the lake is not an exact arrival address, and different access points can produce different plans.
Give lunch enough room
Make one meal the centre of the visit. Ask what is available, whether advance orders help and where the group can sit before and after eating. This is particularly useful if people want to arrive at different times.
If an activity on the water interests you, arrange it separately with an operator and ask about equipment and conditions. A photograph of other visitors doing something doesn't establish what is available for your date.
Avoid a city appointment immediately afterwards
A rest day loses its purpose when the group has to leave early for a fixed shopping stop. Keep the return flexible within the limits of your transport arrangement.
Save Lake Bosomtwe, then add the exact venue details once confirmed. Bring something you enjoy doing while sitting outside. Giving yourself permission to stay in one place is the point of choosing this day.