For example, things you do often but not often enough to make a muscle memory? On Linux systems with Bash, I just use bash aliases. If I do it more than once, It gets an alias or a script; cause I won't remember next time. Example of my current desktop aliases :

alias fuck='sudo $(history -p \!\!)'
alias hstat='curl -o /dev/null --silent --head --write-out '\''%{http_code}\n'\'''
alias ls='ls -la --color=auto'
alias pwgen='< /dev/urandom tr -dc "_A-Z-a-z-0-9\#\+=\$" | head -c${1:-15};echo;'
alias rsync='rsync -ah --info=progress2'

And in my bashrc I have the following settings and functions which come in handy when heads down in the terminal:

# append to the history file, don't overwrite it
shopt -s histappend

# for setting history length see HISTSIZE and HISTFILESIZE in bash(1)
HISTSIZE=1000
HISTFILESIZE=2000
HISTTIMEFORMAT="%Y-%m-%d %T "

####
function stopwatch() {
    local BEGIN=$(date +%s)
    echo Starting Stopwatch...

    while true; do
        local NOW=$(date +%s)
        local DIFF=$(($NOW - $BEGIN))
        local MINS=$(($DIFF / 60))
        local SECS=$(($DIFF % 60))
        local HOURS=$(($DIFF / 3600))
        local DAYS=$(($DIFF / 86400))

        printf "\r%3d Days, %02d:%02d:%02d" $DAYS $HOURS $MINS $SECS
        sleep 0.5
    done
}

function md() {
  pandoc "$1" | lynx -stdin;
}

function weather() {
  ( IFS=+; curl wttr.in/$(curl -s http://ipwho.is/ | jq .postal););
}

So what do you do to remember or recall your most used commands?