Thinking of doing this as I'd quite like to get stronger over all not just build size.
been going to the gym for a fair chunk of this year but never done squats, or OHP and only did dead lifts a few times months a go when I had a different gym partner.
Does it work better than isolation, also I normally go the gym after work so Monday,Tuesday,Wednesday, Thursday. Do you need a rest day in between each day of this? or would i be ok with say Monday, Tuesday, Thursday?
Strong Lifts is built on a solid idea. Follow it from the beginning if you can for two reasons;
1: it will allow you to practice and perfect the lifts (squats especially - over a few weeks with increasing weight you'll find out the most comfortable foot placement/angle etc).
2: As SL uses compound lifts which work multiple muscle groups, starting from the beginning means as you increase the weights over the weeks you'll be strengthening muscles you may not have previously been utilising with regular gym/machine routines.
Whats a compound lift? Basically means your using multiple muscle groups to perform the lift = muscles are being activated = you get a LOT stronger.
Theres a whole bunch of guys who can do endless dumbbell curls and have huge biceps, endless leg extensions using a machine and have huge quads... great for posing but not so great for strength.
From the bottom up;
Dead Lift: uses leg, lower and upper back and forearms.
Squat: uses legs, lower and upper back, abs.
Pendelay Row/Row: uses legs, lower and upper back, abs, arms.
Bench Press: uses arms, chest, abs (core muscles, stability).
OH Press, uses abs (core muscles, stability), upper back, arms.
So you can see why there are squats in every workout, they utilise a lot of muscles! Then the alternations between OHP and Dealift one day, the next Bench and Rows .... working similar groups across the week for a full body workout.
After 5 squats I always do 5 calf raises using the same weight. I also do Dips after every session as a little extra or as I'm getting stronger I'm adding in some pull ups
To start with Mon, Tue Thur will be fine, as the weights get heavier you will want to have a day rest between each session, you'll understand why when you struggle to finish the last 5 squats ... you REALLY wont want to do 25 quats the next day

Same again for OHP and BP. Rest is important to heal as is a balanced diet.
GL and post your progress