I guess this sentence is okay, but I'm not absolutely sure of your intended meaning of "having a plan and trying to do it". Why not say simply,
"I have a plan and am trying to carry it out."
or"I will schedule some time to work on / Carry out the plan."
Your subject line indicates your question is about putting something into your schedule. Yes, you can say, "I'll put the plan into my schedule." Maybe the problem is that I don't quite know what your mean by "put the plan into your schedule", because usually we put items meetings, arrangements into a schedule, not a plan.