buying shares

[novar]

Please proofread my sentences and tell me if they do sound natural.
1. Somehow he managed to convince a lot of people of it bit by bit to buy more of these shares.
2. Somehow he managed to convince a lot of people of it to buy more of these shares bit by bit.
3. Bit by bit he somehow managed to convince a lot of people of buying more of these shares.
4. Bit by bit/Little by little he somehow managed to convince a lot of people of it to buy more of these shares.

 

[Raymott]

"Somehow he gradually managed to convince a lot of people [of it and] to buy more of these shares."

None of them sound natural. "Bit by bit" is confusing in a sentence like that. It makes an ungrammatical sentence even more confusing.
"Of it" doesn't fit. He could have convinced them of two things - "of it" and to buy more shares - but you'd need to use a conjunction or some other grammatical means to show you mean both.