Drawing a loop diagram with nodes

Question

Ok, I have another question. I can make a loop diagram with the matrix way:

However working with nodes seems way more convenient, this is my code:

\documentclass[12pt, letterpaper, twoside]{article}
\usepackage{tikz}
\usetikzlibrary{shapes.geometric, arrows}
\begin{document}
\tikzstyle{startstop} = [rectangle, rounded corners, minimum width=3cm, minimum height=1cm,text centered, draw=black, fill=red!30]
\tikzstyle{io} = [trapezium, trapezium left angle=70, trapezium right angle=110, minimum width=3cm, minimum height=1cm, text centered, draw=black, fill=blue!30]
\tikzstyle{process} = [rectangle, minimum width=3cm, minimum height=1cm, text centered, draw=black, fill=orange!30]
\tikzstyle{decision} = [diamond, minimum width=3cm, minimum height=1cm, text centered, draw=black, fill=green!30]
\tikzstyle{arrow} = [thick,->,>=stealth]
\begin{tikzpicture}[node distance=2cm]
    \node (start) [startstop] {Start};
    \node (in1) [io, below of=start] {Input};
    \node (pro1) [process, below of=in1] {Loop start};
    \node (pro2) [process, below of=pro1] {Process 1};
    \node (pro3) [process, below of=pro2] {Process 1};
    \node (dec1) [decision, below of=pro3, yshift=-0.5cm] {Decision 1};
\draw [arrow] (start) -- (in1);
\draw [arrow] (in1) -- (pro1);
\draw [arrow] (pro1) -- (pro2);
\draw [arrow] (pro2) -- (pro3);
\draw [arrow] (pro3) -- (dec1);

\end{tikzpicture}
\end{document}

I tried to apply the same technique that I used with the matrices but there were cryptic errors about an undefined control sequence...

So, what is the best way to add a rectangular connector with a little no (or yes) on it?

Answer 1

Sorry, your question is not clear. Your MWE is not close to showed image, description of your problem problem is unclear. So, see if the following MWE, based on guessing and on my answer to the similar question, gives what you after:

\documentclass[border=3mm, tikz]{standalone}
\usetikzlibrary{arrows.meta,
                chains,
                positioning,
                quotes,
                shapes.geometric}
\begin{document}
%---------------------------------------------------------------%
% based on:
% http://tex.stackexchange.com/questions/300759/write-easily-a-tikz-flowchart/300829#300829
%---------------------------------------------------------------%
    \begin{tikzpicture}[
    node distance = 6mm and 18mm,
      start chain = A going below,
%
   arr/.style = {-Straight Barb, semithick},
  base/.style = {draw, minimum width=32mm, minimum height=8mm,
                 align=center, on chain=A, join=by arr},
startstop/.style = {base, rounded corners, fill=red!30},   % <---
  process/.style = {base, fill=orange!30},                 % <---
       io/.style = {base, trapezium, trapezium stretches body,
                    trapezium left angle=70, trapezium right angle=110,
                    fill=blue!30},
 decision/.style = {base, diamond, fill=green!30},
every edge quotes/.style = {auto=right, font=\small}
                    ]
\node [startstop]       {input};            % <-- A-1
\node [process]         {Loop start};
\node [process]         {1};
\node [process]         {2};
\node [decision]        {Yes or No ?};
\node [startstop]       {Stop};              % <-- A-6
%%
\draw[arr]  (A-5.west)  to ["No"] ++ (-1.8,0) |- (A-2); % feedback loop
\path       (A-5)       to ["Yes"]  (A-6); 
    \end{tikzpicture}
\end{document}

Answer 2

Alright, added [xshift=7mm] and now it works:

    \draw [arrow] (dec1) -- node[anchor=north] {Yes} ([xshift=7mm] dec1.east) -- ([xshift=7mm] pro1.east) -- (pro1);

Is this the best way though?