if you have lots of money, it is good to hold bitcoin. but if you do not have money, it is better to grow bitcoin than just hold.
so when you grow and make a profit, you can save the most and hold for the long term.
Even if you have a lot of money but still it is better to keep them growing, if you dont want to risk them all then just do it with a half or just with a quarter of what you have, in that way if the price even drops in future you won't be in loss because you have been growing your bitcoins gradually with the time and if the price grows then you will earn a lot more profits then usual.
Holding is very simple, it just needs some patience, it is not necessary that you sell every time there is a price increase because that inrease could be more when you wait for a longer time, one should know how to have patience and treat his investment like a time deposit where there should be a definite time before you withdraw.
Yes if you are looking for higher profits then you need to hold your coins for really long time, as it is predicted that bitcoin has potential to touch $5k in next 5 years.