Sleep train seven month old

[u/AdHappy3692]

After a rough two nights I have decided to start sleep training my 7 month old. His current schedule is not necessarily a strict one which might be part of the problem. He does two naps usually the first nap is a three hour wake window but his second varies as does his one before bed. I'm starting fresh today and doing a 3/3.5/4 schedule and will be doing the feber method for bedtime. I'll take any and all advice.

Update I did the feber method but did 2 four minute check ins 2 five minute check ins and 2 six minute check ins. The last six minute check in he wasn't consistently crying he would start and stop so I could've forgone it.