diff --git a/CHANGELOG.md b/CHANGELOG.md
index 26609ce..c8b904e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 - Added Options.MinIdleConns.
 - Added Options.MaxConnAge.
 - PoolStats.FreeConns is renamed to PoolStats.IdleConns.
+- Add Client.Do to simplify creating custom commands.
 
 ## v6.13
 
diff --git a/cluster.go b/cluster.go
index 863e69a..e68cb7e 100644
--- a/cluster.go
+++ b/cluster.go
@@ -898,6 +898,13 @@ func (c *ClusterClient) Close() error {
 	return c.nodes.Close()
 }
 
+// Do creates a Cmd from the args and processes the cmd.
+func (c *ClusterClient) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
 func (c *ClusterClient) WrapProcess(
 	fn func(oldProcess func(Cmder) error) func(Cmder) error,
 ) {
@@ -1242,7 +1249,7 @@ func (c *ClusterClient) defaultProcessPipeline(cmds []Cmder) error {
 		cmdsMap = failedCmds
 	}
 
-	return firstCmdsErr(cmds)
+	return cmdsFirstErr(cmds)
 }
 
 func (c *ClusterClient) mapCmdsByNode(cmds []Cmder) (map[*clusterNode][]Cmder, error) {
@@ -1424,7 +1431,7 @@ func (c *ClusterClient) defaultProcessTxPipeline(cmds []Cmder) error {
 		}
 	}
 
-	return firstCmdsErr(cmds)
+	return cmdsFirstErr(cmds)
 }
 
 func (c *ClusterClient) mapCmdsBySlot(cmds []Cmder) map[int][]Cmder {
diff --git a/command.go b/command.go
index 8928b8a..7521eae 100644
--- a/command.go
+++ b/command.go
@@ -25,7 +25,7 @@ type Cmder interface {
 	readTimeout() *time.Duration
 
 	Err() error
-	fmt.Stringer
+	//	fmt.Stringer
 }
 
 func setCmdsErr(cmds []Cmder, e error) {
@@ -36,7 +36,7 @@ func setCmdsErr(cmds []Cmder, e error) {
 	}
 }
 
-func firstCmdsErr(cmds []Cmder) error {
+func cmdsFirstErr(cmds []Cmder) error {
 	for _, cmd := range cmds {
 		if err := cmd.Err(); err != nil {
 			return err
@@ -167,8 +167,77 @@ func (cmd *Cmd) Result() (interface{}, error) {
 	return cmd.val, cmd.err
 }
 
-func (cmd *Cmd) String() string {
-	return cmdString(cmd, cmd.val)
+func (cmd *Cmd) String() (string, error) {
+	if cmd.err != nil {
+		return "", cmd.err
+	}
+	switch val := cmd.val.(type) {
+	case string:
+		return val, nil
+	default:
+		err := fmt.Errorf("redis: unexpected type=%T for String", val)
+		return "", err
+	}
+}
+
+func (cmd *Cmd) Int64() (int64, error) {
+	if cmd.err != nil {
+		return 0, cmd.err
+	}
+	switch val := cmd.val.(type) {
+	case int64:
+		return val, nil
+	case string:
+		return strconv.ParseInt(val, 10, 64)
+	default:
+		err := fmt.Errorf("redis: unexpected type=%T for Int64", val)
+		return 0, err
+	}
+}
+
+func (cmd *Cmd) Uint64() (uint64, error) {
+	if cmd.err != nil {
+		return 0, cmd.err
+	}
+	switch val := cmd.val.(type) {
+	case int64:
+		return uint64(val), nil
+	case string:
+		return strconv.ParseUint(val, 10, 64)
+	default:
+		err := fmt.Errorf("redis: unexpected type=%T for Uint64", val)
+		return 0, err
+	}
+}
+
+func (cmd *Cmd) Float64() (float64, error) {
+	if cmd.err != nil {
+		return 0, cmd.err
+	}
+	switch val := cmd.val.(type) {
+	case int64:
+		return float64(val), nil
+	case string:
+		return strconv.ParseFloat(val, 64)
+	default:
+		err := fmt.Errorf("redis: unexpected type=%T for Float64", val)
+		return 0, err
+	}
+}
+
+func (cmd *Cmd) Bool() (bool, error) {
+	if cmd.err != nil {
+		return false, cmd.err
+	}
+	switch val := cmd.val.(type) {
+	case int64:
+		return val != 0, nil
+	case string:
+		return strconv.ParseBool(val)
+	default:
+		err := fmt.Errorf("redis: unexpected type=%T for Bool", val)
+		return false, err
+	}
 }
 
 func (cmd *Cmd) readReply(cn *pool.Conn) error {
diff --git a/example_test.go b/example_test.go
index 7d8cc52..3363b11 100644
--- a/example_test.go
+++ b/example_test.go
@@ -420,6 +420,12 @@ func Example_customCommand() {
 	// Output: "" redis: nil
 }
 
+func Example_customCommand2() {
+	v, err := client.Do("get", "key_does_not_exist").String()
+	fmt.Printf("%q %s", v, err)
+	// Output: "" redis: nil
+}
+
 func ExampleScanIterator() {
 	iter := client.Scan(0, "", 0).Iterator()
 	for iter.Next() {
diff --git a/redis.go b/redis.go
index 4747ff9..2913938 100644
--- a/redis.go
+++ b/redis.go
@@ -123,8 +123,17 @@ func (c *baseClient) initConn(cn *pool.Conn) error {
 	return nil
 }
 
+// Do creates a Cmd from the args and processes the cmd.
+func (c *baseClient) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
 // WrapProcess wraps function that processes Redis commands.
-func (c *baseClient) WrapProcess(fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error) {
+func (c *baseClient) WrapProcess(
+	fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error,
+) {
 	c.process = fn(c.process)
 }
 
@@ -243,7 +252,7 @@ func (c *baseClient) generalProcessPipeline(cmds []Cmder, p pipelineProcessor) e
 			break
 		}
 	}
-	return firstCmdsErr(cmds)
+	return cmdsFirstErr(cmds)
 }
 
 func (c *baseClient) pipelineProcessCmds(cn *pool.Conn, cmds []Cmder) (bool, error) {
diff --git a/ring.go b/ring.go
index 7486202..3ded280 100644
--- a/ring.go
+++ b/ring.go
@@ -516,7 +516,16 @@ func (c *Ring) cmdShard(cmd Cmder) (*ringShard, error) {
 	return c.shards.GetByKey(firstKey)
 }
 
-func (c *Ring) WrapProcess(fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error) {
+// Do creates a Cmd from the args and processes the cmd.
+func (c *Ring) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+func (c *Ring) WrapProcess(
+	fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error,
+) {
 	c.ForEachShard(func(c *Client) error {
 		c.WrapProcess(fn)
 		return nil
@@ -602,7 +611,7 @@ func (c *Ring) defaultProcessPipeline(cmds []Cmder) error {
 		cmdsMap = failedCmdsMap
 	}
 
-	return firstCmdsErr(cmds)
+	return cmdsFirstErr(cmds)
 }
 
 func (c *Ring) TxPipeline() Pipeliner {
diff --git a/sentinel.go b/sentinel.go
index 12c29a7..ef0e470 100644
--- a/sentinel.go
+++ b/sentinel.go
@@ -92,7 +92,7 @@ func NewFailoverClient(failoverOpt *FailoverOptions) *Client {
 		},
 	}
 	c.baseClient.init()
-	c.setProcessor(c.Process)
+	c.cmdable.setProcessor(c.Process)
 
 	return &c
 }