when to add skill points and sell low quality players

hey guys , i'm new on the game level 1 going level 2 next season 1st place and i need help on when to add the skill points to my players , What should i do ...add them everyday as i go and train or save them til the end of the season ?
Also i've got 3 low quality players should i sell them now or after the new season starts ? Thank you :)

i add them everyday ,and yes sell them if you have enough players for the next season.

In the beggining of Every season the price of the players will decrease depending on age and training speed, and If you go up one level they also lose a star, but the Q is the same.
You need to have 14 players with contract signed at the beggining of every season.
If you do not need them, try to sell them now, but it is not easy selling low quality players on level 1, so you probably will be more lucky at the beggining of next season.

myself i save each season depending on league and add if doing badly if doing well save but when i add on first day of new season i make sure i renew contracts first as it will be cheaper to resign player/players at the moment i have over 2000 skill point`s

for level 1. keep 11 best players and 3 worst ( if you don't have, sign Q10-12 player ) sell all the others, if nobody buy them then SACK them all. you will have chance to win the cup. lol

Thanks guys ! :)
I decided to keep those 3 players as tongly45 said i might have a chance to win the cup :) also i'm thinking about adding my skill points every 3 or 4 days :) thanks so much for replies god bless