“Many fine/great things can be done in a day if you don’t always make that day tomorrow” is an anti-proscrastination saying that has been printed on many images. “Lots of things can be done in a day if you don’t always make that day tomorrow” was printed in the syndicated “Barbs” column, written by Hal Cochran,  and was appeared in the Kingston (NY) Daily Freeman on November 7, 1955.
   
“Many fine things can be done in a day if you don’t always make that day tomorrow” was printed in the syndicated “Office Cat, by Junius” column, and appeared in The Daily Times (New Philadelphia, OH) on June 9, 1956.
 
“RT @NancyPerez: Many great things can be done in a day if you don’t always make that day tomorrow” was posted on Twitter by Shakthi Vadakkepat on June 30, 2009.
 
     
Newspapers.com     
7 November 1955, Kingston (NY) Daily Freeman, “Barbs” by Hal Cochran, pg. 14, col. 1:
Lots of things can be done in a day if you don’t always make that day tomorrow.
     
Newspapers.com
9 June 1956, The Daily Times (New Philadelphia, OH), “Office Cat,” pg. 4, col. 1:
Many fine things can be done in a day if you don’t always make that day tomorrow.
     
Google Books
Norfolk and Western Magazine
Norfolk and Western Railway Company
Volume 34
1956
Pg. 756:
Many fine things can be done in a day if you don’t always make that day tomorrow. — Tit Bits, London
 
Google Books
New Treasury of Stories for Every Speaking and Writing Occasion
By Jacob Morton Braude
Englewood Cliffs, NJ: Prentice-Hall
1959
Pg. 310:
Many fine things can be done in a day if you don’t always make that day tomorrow.
—Tit-Bits, London
   
18 August 1975, Las Vegas (NV) Sun, “Your Next Door Neighbor” bu Chuck Burface, pg. 4, col. 5 ad:
Sudden Thought: Many fine things can be done in a day—if you don’t always make that day tomorrow.
 
Twitter
Giovanna Pang Garcia
@giovannagarcia
“Many fine things can be done in a day if you don’t always make that day tomorrow.”
11:25 AM - 23 Oct 2008
   
Twitter
Rob Northrup
@RobNorthrup
“Many fine things can be done in a day if you don’t always make that day tomorrow” - unknown
9:41 AM - 13 Jan 2009
     
Twitter
Shakthi Vadakkepat
@v_shakthi
RT @NancyPerez: Many great things can be done in a day if you don’t always make that day tomorrow.
10:39 AM · Jun 30, 2009·Twitter Web Client
 
Google Books
Have You Discovered Your Assignment with Destiny?
By Anthony Ugochukwu Aliche
Bloomington, IN: iUniverse
2012
Pg. 81:
“Many fine things can be done in a day if you don’t always make that day tomorrow.”
Anonymous
     
Google Books
Diamond In The Rough Unveiled
By Balderes Lucila Santos de Alvarez
Victoria, BC: Trafford Publishing
2013
Pg. 73:
Many great things can be done in a day if you don’t make that day tomorrow” (unknown).
 
NBC4 (Washington, DC)
10 Hard Things to Start Doing for Yourself
By Marc Chernoff • Published at 5:48 am on September 26, 2017
(...)
Many great things can be done in a day if you don’t always make that day tomorrow. Take positive action and plant the right seeds in your life right now.
 
Twitter
Xan Ria
@xanria_018
#ALDUBComeBackSoon
Many fine things can be done in a day if you don’t always make that day tomorrow.
8:27 AM - 14 Apr 2018